by Adriana Lopez-Villalobos and Amelie Mahrt-Smith
If you’ve ever thought of planting flowers to attract pollinators to your garden, milkweed should be on top of your list – plants in the genus Asclepias are known for attracting all kinds of insects, most notably the monarch butterfly. The common milkweed, A. syriaca, is estimated to provide food to over 450 different species of insects! [3] Asclepias is a member of the Apocynaceae family, also known as the dogbane family. While they may provide adequate food for pollinators, some taxa are poisonous to animals – the family gets its colloquial name from those taxa that were historically used as dog poison [6]. The genus name, Asclepias, comes from the Greek god Asklepios the god of medicine. Milkweed has had a variety of uses in human culture over the years; medicine is just the beginning.
Common milkweed, Asclepias syriaca, growing by a riverbank in Kingston, ON.
The flowers of Asclepias are morphologically distinct. They are clustered in heads called umbels, with 30-50 individual flowers in each. The image below shows a close up of several A. syriaca flowers and their characteristics. The petals (a) are reflexed downward toward the stem, and a petal-like shape is made by the corona, which is made up of five nectar-secreting hoods (b) and incurving horns (c). The floral corona helps to attract pollinators. Pollen is produced in the anther (d) and received by the stigmatic disc (e). In Asclepias, these structures are fused into a single structure called the gynostegium. Between two adjacent anthers forms the anther wings (f), which enclose a stigmatic chamber. Above this chamber is the pollinium gland (g), where pollen can be retrieved[4]. All of the flower buds in an umbel will open within 2-3 days of each other, and fade in colour and begin to shrivel shortly after being pollinated [5]. Not every flower will produce seeds, even if they have been pollinated – one stem may have 50 flowers but still only produce one or two seed pods.
LEFT: Close up of A. syriaca inflorescence, showing the different parts of the individual flower. RIGHT: Seed pods ripening on an A. syriaca individual.
Pollinators searching for nectar on the unstable flowers can get pollinia, a mass of pollen grains, stuck to the adhesive pads on their feet that help them climb. These pollen grains may be deposited on the stigmatic disc of another flower as the insect continues to forage [4]. While they are visited by bumblebees, wasps, ants, and flies as well, milkweed is most commonly associated with the butterflies that are attracted to the sweet-smelling flowers. The iconic monarch butterfly relies on milkweed for its entire life cycle. The eggs are laid on the underside of milkweed leaves, which the caterpillars eat from when they hatch. The poisonous compounds in Asclepias, chemicals called cardiac glycosides, are actually used by the caterpillars as a defence mechanism against predators. Insects like the monarch caterpillar that are adapted to feeding on Asclepias plants store these compounds in their body instead of metabolizing them, which effectively makes them poisonous to those looking for a tasty grub to snack on [1]. After metamorphosis, the monarch butterfly may eat the nectar from milkweed flowers in addition to many other species, but it will always return to milkweed to lay its eggs.
Although toxic in large quantities, the compounds in milkweed have given them traditional medicinal uses in human culture. A. syriaca, the common milkweed, was used by colonial settlers as an expectorant, an emetic, and a remedy for asthma. A related plant, A. tuberosa, has been used to induce perspiration and in the treatment of lung ailments. The milky latex produced by the plant, which can be seen oozing from the stem if one breaks off a leaf or flower, was investigated as a rubber precursor but was never profitable. The seed hair fibres were used as a wartime substitute for kapok to make life jackets [2]. Although not profitable for humans, milkweed is still a very important plant for pollinators like the monarch butterfly.
Asclepias syriaca is native to North America and is commonly found invading fields and roadsides. This specimen was collected at QUBS in 1960 by the former curator, Roland Beschel. You can find A. syriaca in flower all around QUBS from July to early August!
A specimen of A. syriaca collected at QUBS in 1960.
Moore, R.J. 1946. Investigations on rubber-bearing plants. V. Notes on the flower biology and pod yield of Asclepias syriaca L. Can. Field Natur. 61: 40 – 46.
Macior, L.W. 1965. Insect adaptation and behavior in Asclepias pollination. Bull. Torrey Bot. Club, 92:114 – 126.
Gaertner E.E. 1979. The history and use of milkweed (Asclepias syriaca L.). Economic Botany 33: 119-123.
Erickson, J.M. 1973. The utilization of various Asclepias species by larvae of the monarch butterfly, Danaus plexippus. Psyche A Journal of Entomology 80(3) DOI: 10.1155/1973/28693
by Adriana Lopez-Villalobos and Amelie Mahrt-Smith
Fans of alternative medicine are likely familiar with the mint family, the Lamiaceae. Many of these plants produce essential oils used to battle ailments or boost the immune system – for example, oil of oregano is a common herbal treatment for sore throats, and peppermint oil has a cooling effect that can alleviate sore muscles. Lamiaceae plants are also widely used to add flavour to dishes and drinks, such as sage and rosemary – both in the genus Salvia. Among the other curious properties of the plants in this genus, Salvia divinorium (sometimes known as sage of the diviners or simply Salvia) is psychoactive and is recreationally smoked, chewed or consumed as a tea to induce hallucinations.
There are a variety of chemical compounds responsible for the different properties of plants in the Lamiaceae family. Within the Nepetoidae subfamily, which contains many of the more familiar Lamiaceae plants, the phenolic compound rosmarinic acid is mainly responsible. It was named after the plant from which it was first isolated, Salvia rosmarinus, also known as rosemary. This acid has shown antiviral, antimicrobial, and antioxidant activities. It has also been reported to deter pests like the tobacco hornworm (Manduca sexta).(4) Plants containing rosmarinic acid are most used to treat inflammation – and advances in molecular genetics help to explain why they are effective. In basic terms, rosmarinic acid stops the production of compounds that initiate inflammatory responses when cells are under stress – for example, from a viral infection. The acid inhibits the genes that tell the cell to make inflammation-inducing compounds and thus eases the symptom.(2)
Unsurprisingly, the Lamiaceae have been used in traditional medicine around the world for generations. The common characteristics of this family may have helped early peoples to recognize that a variety of different species can be used for food and medicine – the resemblance between species is strong, especially as you move from the family to the subfamily or to the genus level. Plants in the mint family usually have simple leaves, and they are always oppositely arranged. The stems are usually four-angled, with the leaves at each node being rotated 90° so that the leaves grow in four directions away from the stem. The flowers, which can be hermaphrodite or functionally female (i.e. The male parts are sterile), usually have five lobes and two ‘lips’ – hence the synonym Labiatae which is sometimes used to describe this family. The plant itself often has dense glands and a strong aroma.(3) Using these characteristics, you can identify common plants in the mint family that may be growing around your neighbourhood!
Glechoma hederacea – Ground Ivy
A native to Europe, G. hederacea is a creeping herb that was brought over deliberately by settlers for medicinal use and food and it quickly invaded the North American lands. It is low to the ground and inconspicuous – it can be recognized by its oppositely arranged, kidney-shaped leaves with blunt teeth, and blue-violet flowers about ½ inches long. It flowers in late spring and early summer, and by this time of year has already set seed. The upper lip of the corolla has three lobes that appear to be three distinct petals; the lower lip has two lobes with spots that are usually purple but occasionally pink or white. It flowers early in spring, and by mid-summer has produced seeds. However, it spreads much more rapidly by producing clones than seed dispersal. It is also suspected to have allelopathic effects, which helps it outcompete other plants and rapidly take over an area.(1)
Glechoma hederacea is a member of the Nepetoideae subfamily, so the presence of rosmarinic acid and other chemical compounds makes it a good contender for medicinal use. It is an effective anti-inflammatory agent and as such has been used against catarrh, the excess buildup of mucus caused by inflammation of the body’s mucus membranes.
Prunella vulgaris – Self-heal
Named for its ubiquitous use in traditional medicine, the selfheal is a Holarctic species – native to the continents of the northern hemisphere. It is also a member of the Nepetoideae subfamily and contains rosmarinic acid as the major phenolic compound. It has been said to treat sore throats, fevers, and accelerate wound healing.(5) Prunella vulgaris has also been shown to have specific activity against herpes simplex virus (HSV). Chemical compounds produced by the plant are shown to be effective at reducing the viral load of cells infected with HSV and has the potential to be used as an antiviral treatment for cold sores.(6)
The leaves are lance-shaped and entire, arranged oppositely as is typical of the Lamiaceae. The flowers are violet or purple and found in short spikes. It flowers from late spring to fall and can be found along roadsides and in waste places throughout Kingston, ON right now!
Because of the widespread medicinal and culinary uses of plants in the Lamiaceae family, European colonists brought many of them around the world with them. In addition to intentional introductions, seeds and fragments of plants can hitchhike along with other biological materials brought by settlers. For example, Lamium amplexicaule, also known as common dead-nettle is one of many members of the Mint family that was introduced to North America from the Old World. This specimen was collected in Kingston by George Lawson in 1859. Lawson was appointed professor of Chemistry and Natural History at Queen’s University in 1858, where he set up a botanical laboratory. He was also a founding member the Botanical Society of Canada, established in 1860. His wife, Mrs. Lawson, was an amateur botanist, and inspired equal privileges for female members of the Society. He was an ambitious man and saw the Botanical Society as a means of encouraging botanical research beyond the British settlements in Canada.(7) Although he only stayed a few years at Queen’s before moving on to Dalhousie University, his legacy remains at Queen’s in the specimens that are kept within the Fowler Herbarium.
References
Hutchings, M. J., and E. A. C. Price. 1999. Glechoma hederacea L. (Nepta Glechoma Benth., N. hederacea (L.) Trev.). Journal of Ecology 87:347 – 364.
Kim, J., S. Song, I. Lee, Y. Kim, I. Yoo, I. Ryoo, and K. Bae. 2011. Anti-inflammatory activity of constituents from Glechoma hederacea var. longituba. Bioorganic & Medicinal Chemistry Letters 21:3484 – 3487.
Kokkini, S., R. Karousou, and E. Hanlidou. 2003. Herbs of the Labiatae. Pages 3082 – 3090 in L. Trugo, and P. M. Finglas, editors. Encyclopedia of Food Sciences and Nutrition (Second Edition). Academic Press.
Petersen, M., and M. S. J. Simmonds. 2003. Rosmarinic acid. Phytochemistry 62:347 – 364.
Psotoyá, J., M. Kolář, J. Soušek, Z. Švagera, J. Vičar, and J. Ulrichová. 2003. Biological activities of Prunella vulgaris. Phytotherapy Research 17:1082 – 1087.
Xu, H., S. H. S. Lee, S. F. Lee, R. L. White, and J. Blay. 1999. Isolation and characterization of an anti-HSV polysaccharide from Prunella vulgaris. Antiviral Research 44: 43 – 54.
by Adriana Lopez-Villalobos and Amelie Mahrt-Smith
Image 1. Shepherd’s Purse, Capsella bursa-pastoris, growing between the cracks of the sidewalk on Garrett St. in Kingston, ON
Capsella bursa-pastoris may at first appear to be just another weed blending into the sea of fresh spring greenery. But take a closer look at this plant commonly known as Shepherd’s Purse, and you will notice the curious appendages from which it got its name. Its distinctive seed pods – small pouches in the shape of a heart – bear resemblance to an old-fashioned style of purse carried by shepherds in centuries past [6]. This widespread edible weed is a part of the Mustard family, Brassicaceae. This family is shared by garlic mustard (see our previous post about it), thale cress, and many common supermarket vegetables like broccoli and kale. Of the five species in the Capsella genus, C. bursa-pastoris is the only one found in North America, which makes it easier to identify this species in your community.
Image 2. Notice the large, irregularly lobed basal leaves and smaller, clasping stem leaves (left); as well, the small cluster of white flowers at the tip and the ‘purse-shaped’ seed pods emerging laterally from the stem (right).
Shepherd’s Purse is a cosmopolitan weed: it is found all over the world. Its secret weapon is its ability to grow in a wide variety of conditions. It can be found in disturbed ground or dumps, and frequently invades the cultivated soil in gardens and crops. It can grow in full sun or partial shade, dry or moist soils, and even cracks in concrete (Image 1); its hardiness makes it a good contender for urban living [3]. You can identify Shepherd’s purse by its large leaves with irregular lobes at the base of the stem, and smaller, arrow-shaped leaves that clasp the stem. In good conditions, it can reach 60-80 cm tall. Its tiny white clustered flowers have four petals each (with the 6 distinctive stamens: 2 outer short and the 4 inner long). The most identifiable feature is the heart-shaped seed pods attached to the main stem by a long stalk, which makes it distinguishable from similar plants like wild mustard (Image 2) [5]. Early in the spring, Shepherd’s Purse’s flowers begin to bloom, and they will continue to bloom until late fall. It is an annual, which means an individual plant only survives for one year, but several generations can be produced during the warmer months, and a single plant can produce up to 45,000 seeds! This is a high level of production that is facilitated, in part, by their ability to self-pollinate. Instead of waiting for an insect to come by and transfer pollen from one individual to another, the pollen simply fertilizes the flower from which it was produced (or a close neighbouring flower) [4].
Image 3. A Shepherd’s Purse plant collected in 1862, specimen is part of the Fowler Herbarium collection at QUBS. Click on thumbnail for larger image.
C. bursa-pastoris was introduced to North America by European settlers many times over. In the southwestern United States, it hitched a ride with Spanish colonizers, while further north in the U.S. and Canada, we have the British and French colonists to blame [7]. Shepherd’s Purse was once an important European medicinal herb, especially for women. Like many plants, has been overtaken by more effective modern drugs. All its parts are edible and can be used as a peppery seasoning – although we do not recommend you try this with unfamiliar plants! The leaves, which are high in vitamins and minerals, were traditionally made into a tea for the relief of pre-menstrual cramps and to reduce the risk of haemorrhaging after childbirth [1,2]. The Fowler Herbarium at the Queen’s University Biological Station has C. bursa-pastoris specimens collected in Kingston during the 1800s. This beautifully preserved Shepherd’s Purse specimen was collected in 1862 in the former township of Ramsay, Lanark County, which lies between modern-day Kingston and Ottawa. Notice the defining features of C. burasa-pastoris: the larger basal leaves, small stem leaves, heart-shaped seed pods, and clusters of tiny flowers at the tip (no longer white, but you get the idea.
References
Aksoy, A., Dixon, J.M. and Hale, W.H. 1998. Biological flora of the British Isles. Capsella bursa-pastoris (L.) Medikus (Thlaspi bursapastoris L., Bursa bursa-pastoris (L.) Shull, Bursa pastoris (L.) Weber). Journal of Ecology 86, 171-186.
Ghalandari, S., Kariman, N., Sheikhan, Z., Mojab, F., Mirzaei, M., and Shahrahmani, H. 2017. Effect of hydroalcoholic extract of Capsella bursa pastoris on early postpartum hemorrhage: A clinical trial study. J Altern Complement Med 23, 794‐799. doi:10.1089/acm.2017.0095
Grieve, M. 1984. A Modern Herbal. Penguin. New York. ISBN 0-14-046-440-9
Newcomb, L. 1977. Newcomb’s Wildflower Guide (pp. 150). Little, Brown and Company. New York.
6. Reader’s Digest Field Guide to the Wild Flowers of Britain. Reader’s Digest. 1981. p. 54. ISBN 9780276002175.
Neuffer, B., and Hurka, H. 1999. Colonization history and introduction dynamics of Capsella bursa-pastoris (Brassicaceae) in North America: isozymes and quantitative traits. Molecular Ecology 8, 1667-1681.
by Adriana Lopez-Villalobos and Amelie Mahrt-Smith
Image 1. Garlic mustard invading a lawn on Bagot Street, Kingston ON. Click on thumb for larger view.
Next time you are out for a walk around the neighbourhood, keep your eyes out for this weed in lawns, empty lots, and along trails. Alliaria petiolata, commonly known as garlic mustard, is in bloom through spring and early summer in Ontario. This widely distributed herb is a member of the Brassicaceae (Mustard) family alongside many well-known, if not well-liked cruciferous vegetables: broccoli, kale, brussels sprouts, turnip, horseradish, and wasabi, to name a few [3]. Garlic mustard gets its name from the garlic smell released by the leaves when crushed; the leaves, as well as the flowers and seeds, are edible and add a mild garlic or mustard flavour to dishes. Make sure to you ask your neighbours if they have used herbicides on their lawn before you try adding garlic mustard leaves to your salad or pesto!
Image 2. Close-up of garlic mustard, Alliaria petiolata, showing its four-petaled white flowers and saw-toothed leaves. Click on thumb for larger view.
Mature garlic mustard plants are easy to identify. The heart-shaped leaves have saw-toothed edges, prominent veins, and long stalks connecting them to the main stem. Leaves are unpaired and alternate in their position on the stem. Its height varies, but in rich soil can reach up to 1 metre tall. The flowers are somewhat inconspicuous: small and white, each with four sepals and petals (both free), and clustered at the tips. As it is typical of the mustard family, the flowers have six stamens (male part) with the two outer stamens shorter than the four inner stamens. These flowers only develop in the plant’s second (and final) year of life (Images 1 and 2). In its first year of growth, the leaves are more rounded and can look like some other common Ontario herbs like violets or wild ginger [4]. Your other senses will come in handy here – you can tell young garlic mustard apart from the rest because its leaves will still have the distinctive garlic smell when crushed.
Despite its abundance in North America today, garlic mustard did not exist here until around the 1800s, when it was purportedly introduced by European settlers who cultivated it for food and medicine. It is a good source of vitamin A and C and was used as an antiseptic to treat ulcers and relieve itching caused by insect bites and stings [2], so it makes sense they would have wanted this useful plant with them in this strange new world. However, since its introduction to North America, A. petiolata has spread vigorously and crowded out some of the native flora, preferentially invading areas of moist soils and shade. Dr. Rob Colautt i of the Queen’s University Biology Department has been investigating the effects of this species on the soil microbial communities as a possible explanation for its rapid invasion [https://www.ecoevogeno.org/research.html]. His research has found that A. petiola does alter some nutrient-cycling bacteria in the soil [4]. We are excited to see the results of his ongoing work!
Image 3. An Alliaria petiolata individual collected in 1886 in Sweden. Click on thumb for larger view.
Herbarium specimens can tell us much about the history of garlic mustard. This specimen from the Fowler Herbarium (Image 3) was collected in Sweden in 1886; back then, the scientific name for this plant was Sisymbrium alliaria (now a taxonomic synonym). As more species and molecular tools are used in taxonomic studies, the names of species sometimes change. Taxonomy is constantly being revised and families, genera and species are continually being re-assigned as a result. Herbaria must be periodically updated with the most recent information – here, we can see that the genus and species was revised by Assistant Curator A.E, Garwood in 1980, and again in 1990 to what is currently the accepted name of the species: Alliaria petiolata (M. Bieberstein) Cavara & Grande. Our efforts to digitize the specimens housed by the Fowler Herbarium have also given us a chance to revise any outdated information in the collection.
Grieve, M. 1984. A Modern Herbal. Penguin. New York. ISBN 0-14-046-440-9
Koch, M., Al-Shehbaz, I.A., and Mummenhoff, K. 2003. Molecular systematics, evolution, and population biology in the mustard family (Brassicaceae). Annals of the Missouri Botanical Garden 90, 151 – 171.
Lavoie, K., Antunes, P.M., and Colautti, R.I. Effects of Alliaria petiolata invasion on soil microbial community structure inferred from bacterial 16S and fungal ITS metabarcodes. (in prep.)
Newcomb, L. 1977. Newcomb’s Wildflower Guide. Little, Brown and Company. New York. pp. 138.
In 1944 Queen’s University bought approximately 26 ha of farmland in Lots 15 and 16 of Concession IX in South Crosby Township as a site for a field station (Smallman et al. 1991). The main interest in the site was its access to Lake Opinicon for aquatic studies led by Dr. Curran, but the land was of interest to Professor Earl, a botanist trained in cytogenetics who was at that time Acting Dean. Neighbouring land belonged to other Queen’s people, Professors Curtis and Smailes.
Since the establishment of the biological station at QUBS Point the area has become more forested after tree planting was implemented and cattle grazing was prevented. It should be noted that White-tailed Deer continue to graze but probably with far less impact on the flora. We discuss three types of evidence that highlight the changes in the vegetation at QUBS Point since the 1940s: memories of local people, maps and aerial photographs and historic field work data.
Memories of local people
In the summer of 1946 Dr. S.R. Brown was at the field station as an undergraduate. He had come to Queen’s as soon as he was demobbed and after finishing his studies here and at Yale he returned and later became the Station Director (Smallman et al. 1991). Dr. Brown remembers that one of his jobs that summer was tree planting, directed by Dr. Earl. The resident students planted rows of Red Pines and Black Walnuts, and possibly some Butternuts, in open fields presumably for shade and eventual economic value. Most of the pines and walnuts were planted in the valley northwest of where Cabins 1-8 now stand, and parallel to the car park. There was also a patch of Red Pines put northeast of Earl Cottage. Later about twenty Hybrid Poplar trees were planted along the edge of the car park; Dr. Brown thinks they came from the University of Toronto where a likely source was Dr. C. Heimburger, a forester who worked on disease resistance in trees.
Figure 1. Tree planting at QUBS Point in 1945. The original caption reads: “Planting trees to stop erosion”. Photo: Wes Curran.
Dale Kristensen (Queen’s University) suggests that the tree planting may have been part of a provincial campaign to control erosion at that period, when conservation authorities were being established in recognition of disasters such as the flooding in the Ganaraska Valley. The caption of one of the historic photographs at QUBS from Wes Curran’s album also suggests this (Figure 1).
When AC first saw these plantings in the late 1960s most of the poplars, which had grown very tall, were diseased and they subsequently died or were felled. At least one large poplar remains at the east end of the main parking lot and another between the workshop and storage building. The Black Walnuts had grown poorly, but their survivors grew large now produce a good crop of nuts annually. The Red Pines were successful in both sites; some have been thinned and some used as poles and many have begun to die back in recent years. The ice storm of 1998 caused considerable damage to the plantations, but in general they still remain intact.
Maps and aerial photographs
Aerial photography by the Royal Canadian Air Force was the basis for the 1:50,000 series of Ontario maps produced in the 1920s and 30s; the Westport sheet (31/C9) which includes Lake Opinicon and environs continued in print until the 1960s. These maps showed coniferous or deciduous forest as different types of tree symbols, spaced by hand to indicate density. Cow Island, the mainland shorelines and northeast part of Queen’s property were drawn with sparse deciduous trees. Red Pines which must have been growing on Cow Island at that time were not noted on the maps.
Figure 2. Aerial photograph taken in autumn 1953 (4425-14-19#132). Note the dense trees in the vicinity of the boathouse, near Cow Island and in two belts parallel to the row of cabins. Between these two belts of trees the lines of the young plantations of pines and walnuts are clear (red arrow). Photo: Royal Canadian Air Force.
An aerial photograph taken in fall 1953 (4425-14-19#132) shows dense trees in the boathouse area, near Cow Island and in two belts parallel to the row of cabins (Figure 2). Between these two belts of trees the lines of the young plantations of pines and walnuts are clear. The trees close to the cabins can be seen in a photograph dated 1945 in Smallman et al. (p149); Ted Brown and A.C. remember a high proportion of basswood in this fringe of trees some of which were later destroyed by a wind storm in the 1980s. In 1973 an aerial survey included QUBS in four sheets (1.71-4-4423-164 and 165, and 1.71-31-4424-65 and 66) but the quality was poor and offer little evidence of changes in tree cover. An aerial photograph taken by AC in July 1980 (Figure 3) shows the plantations as continuous tree cover at that time although the rows were still apparent. Note that new aerial photos of all QUBS properties including QUBS Point can be found on the station website.
Field data: 1945-46
In the 1960s the only two large old trees observed near the station proper were an Eastern White Pine on the rocky shore near Earl Cottage and a White Birch beside an outcrop in the same area. Coring showed both dated to the 1890s. The pine is still flourishing but the birch has subsequently died, apparently from fungal rot.
Figure 3. Aerial photograph from July 1980. The plantation rows are still visible among the continuous vegetation cover. Photo: Adele Crowder.
In 1970 after the death of Dr. R. Beschel, a plant ecologist in the Biology Department, AC was asked to sort his scientific papers and found among them two notebooks labelled “Tree Census Report, Queen’s University Biology Station Summer 1945” and “Summer 1946”. They are hardback notebooks, not field books but tidy ink-written records in two handwritings without any authors’ or owners’ names. Dr. Brown thought that they were probably the work of undergraduates working for Dr. Earl, who presumably gave them to Dr. Beschel.
Neither the purpose nor the method of the survey is described. Dr. Earl conducted forestry and soil studies from 1947 to 1956 employing one or two student assistants each year (Smallman et al. 1991) but we have not found other reports or theses. The first notebook begins with a sketch map of the station, its only built feature being the driveway (Figure 4). Parts of the shore are not solidly outlined. A grid is superimposed on the map, with its axes following the lot line directions. The grid is divided into squares of 250’ x 250’, each subdivided into small squares 50’ x 50’. The large squares must belong to a larger grid since they are numbered 182-217; in the second notebook the numbering was
Figure 4. Reproduction of the sketch maps from the hardback notebooks. The original grid numbering system (from 1945) corresponds to the numbers in purple. A different system was employed in the 1946 survey; those numbers are given in red. One tree symbol represents a density of 1 tree/50 sq ft. Note that the western most squares and #216 were not counted.
changed to 1-49 on another copy of the same map. The small squares, which we shall call quadrats, were numbered 1-25, in vertical rows beginning at the bottom left. Before the UTM grid was adopted in the 1940s the army used a Modified British Grid for its maps, with lines 1000 yds apart (Nicholson and Sebert 1981): as Dr. Earl served in World War I and commanded Queen’s Officers training Corps in World War II he would have been aware of updates in maps with this grid produced by the Army Survey Establishment.
Each page of the notebooks has a column of Latin plant names in alphabetical order followed by vertical columns for seedlings, for two sizes of saplings, for three sizes of trees and for ‘clumps’. Seedlings were described as scarce, few or many. Counts of individual saplings and individual trees were entered in small, medium or large size categories; current definitions include small, medium, large and very large, (Farrar, 2009). The term ‘clumps’ was used only for Common Juniper. Entries were made for 50’x 50’ quadrats, and followed by sums for each large square.
Authorities for the Latin names were not given but the nomenclature followed Native Trees of Canada then available in Douglas Library in several editions. The 1946 edition (J.H. White 1946) defined size categories of trees, but the survey did not appear to use them as the notebooks contain no information on height or diameter at breast height (dbh). Definitions of seedlings vary greatly so that it is impossible to know what criteria were used. The general approach was not that of a forester or a timbercruiser but several texts in Douglas Library provided ecological methodologies of community analysis using transects or quadrats; a likely source for Dr. Earl was Aims and Methods in the Study of Vegetation (Tansley and Chipps 1926) which contains a section on Canadian forestry by C.D. Howe. AC remembers Dr. Earl discussing Tansley’s work.
The students began counting in “Summer 1945” in Square 182 ( renumbered 15) near the Boat House and counted 19 of its 25 quadrats. No compass bearings were given. They then proceeded north to 181(14) beside the lodge, in which three quadrats were not wooded. They then went to the shore at the Boat House and again worked northwards, to the boundary fence with the Curtis property. Their last square was 215 (48) more than half of which is in Cow Island Marsh, and they commented that the shoreline was indefinite with Speckled Alder and Eastern White Cedar swamp. In total they counted 298 quadrats in 21 squares, with the break between years after Square 192(25). A square on Cow Island was counted in 1946 but no location was given for it. They did not go southwest of the lodge, omitting Common Apples and the Bur Oaks near the point. The omission may have been due to lack of time or perhaps avoidance of the new plantations.
The students’ census data are tabulated in Table 1 with Latin and English names. Presence of seedlings in 1945-6 is shown (column A). Saplings are summed as the counts for all squares (Column B): the most abundant were Ironwood, Largetooth Aspen and Sugar Maple. Tree numbers of the three size categories have been lumped together (n=2549); most were in the medium size category, with 276 in the large class. Percentage frequency of species in all the sampled quadrats is shown (Column C); the most frequent were Sugar Maple, Ironwood, Eastern White Cedar, American Basswood and Northern Red Oak, followed by White Birch, Bitternut Hickory, Common White Oak, Largetooth Aspen and Rock Elm.
Table 1. Column A shows presence of seedlings in 1945-46; Y = seedlings present, N = seedlings not present. Column B shows counts of saplings in 298 quadrats in 1945-46. Column C gives percent frequencies of tree species in all quadrats counted in 1945-46 (n=2549). Column D shows presence of seedlings in 1974-78; Y = seedlings present, N = seedlings not present. Column E gives percent frequencies of trees in 1974-78 (n=2121).
Latin Name
English Name
A
B
C
D
E
Abies balsamea
Balsam fir
N
0
0
Y
0
Acer negundo
Manitoba maple
N
1
0.11
N
0
Acer rubrum
Red maple
Y
7
0.27
Y
0
Acer saccharum
Sugar maple
Y
133
26.08
Y
29.46
Alnus rugosa
Speckled alder
Y
0
0.07
N
0.37
Betula allegheniensis
Yellow birch
N
0
0
N
0.09
Betula papyrifera
White birch
Y
0
4.59
Y
5.18
Carpinus caroliniana
Blue-beech
Y
67
1.17
Y
2.31
Carya cordiformis
Bitternut hickory
Y
23
4.74
Y
3.34
Carya ovata
Shagbark hickory
Y
5
0.98
Y
0.23
Corylus americana
American hazel
N
0
0
Y
0.09
Fagus americana
American beech
N
30
1.76
Y
1.6
Fraxinus americana
White ash
Y
23
0.66
Y
4.1
Fraxinus nigra
Black ash
Y
0
0.66
N
0
Fraxinus pennsylvanica
Red ash
N
0
0
Y
1.51
Juglans cinerea
Butternut
N
11
0.19
N
0.09
Juniperus virginiana
Eastern red cedar
Y
42
0.39
Y
0.04
Ostrya virginiana
Ironwood
Y
478
19.49
Y
27.34
Pinus resinosa
Red pine
N
0
0
N
2.26
Pinus strobus
White pine
Y
53
1.37
Y
1.83
Populus balsamifera
Balsam poplar
N
0
0
N
0.23
Populus deltoides
Eastern cottonwood
N
0
0
N
0.37
Populus grandidentata
Largetooth aspen
Y
161
1.72
Y
5.13
Populus tremuloides
Trembling aspen
Y
22
0.31
N
0.42
Prunus serotina
Black cherry
Y
0
0.03
Y
3.06
Quercus alba
White oak
Y
0
2.27
N
0.47
Quercus rubra
Red oak
Y
5
5.21
Y
2.64
Robinia pseudacacia
Black locust
N
0
0
N
0.09
Thuja occidentalis
Eastern white-cedar
Y
0
16.94
Y
3.44
Tilia americana
Basswood
Y
0
7.76
Y
3.67
Tsuga canadensis
Eastern hemlock
N
0
0.9
N
0.09
Ulmus americana
White elm
N
0
1.49
N
0
Ulmus thomasii
Rock elm
N
0
0
N
0
Field Data: 1974 and 1978
When teaching a field course at QUBS in the 1970s AC thought it would be interesting to know the composition of the forest community round the station at that time. At first it seemed possible to resurvey some of the 1940s census with the help of students. However several problems were encountered, the first problem was definitions: what was a sapling, what was a tree?
Figure 5. A 1952 land survey plan showing the new fence line in red. The new fence line made later vegetation surveys in the 1970s very difficult to organize because of confusion over the original grid plan in relation to old and new property lines.
The second problem was location. After wasting a day not being able to match quadrats we found that an accurate geographic survey of the station was not made until 1952 when D.J. Humphries made one drawn to a scale of 1” to 100’, showing astronomic north, with bearings and distances laid down and marsh boundaries, buildings and driveways shown. The lot line bearing was given as N 49o 06’30” E. Most importantly the boundary with Curtis land was redrawn and a new fence line had to be built (Figure 5). Near Cow Island the new fence diminished QUBS land by as much as 240’, thereby excluding much of four of the northern tier of squares of the 1945 sketch map and survey (197, 203, 209, 215). About 20 acres of the purchased 65 were lost (Smallman et al. 1991). Another problem in relocating 1940s quadrats was later disturbances such as hydro lines, new driveways, aviaries and other structures.
AC decided to use the same technique as the 1940s survey, although no statistical comparisons could be made because we would use the smaller area inside the new boundaries and would adopt definitions which would speed up counting. Accordingly seedlings were defined as having four or less foliage leaves, saplings as being less than 1.5 m high, and all tree sizes were lumped. Selection of quadrats was randomly stratified in Squares 12, 13, 14, 18, 20, 24, 26, 31, 32, 37, 42 and 48. Later more quadrats were added in nine of these squares because their ground flora was interesting. Ground flora was listed in all sampled quadrats (n=34). Data from 1974 and 1978 are shown in Table 1 with the reminder that the sampling technique of the 70s was not directly comparable to the census of the 40s, and that the area used was 34 quadrats in the 1970s and 298 in the 1940s. Presence/absence of seedlings in the 1970s is shown (Column D). Species not found as seedlings in either decade were Butternut, Eastern Hemlock and Rock Elm. Seedlings reported only in 1945-6 were Black Ash, Trembling Aspen and White Elm. Seedling species diversity was higher in the 70s with the addition of Balsam Fir, Red Maple, Corylus sp., Red Ash, Balsam Poplar, Eastern Cottonwodd and Black Locust.
A crude estimate of seedling abundance can be made from the 1940s quadrats listed as having ‘many seedlings’. The shade-tolerant Sugar Maple was so described in 21 quadrats in 1945 and 10 in 1946. The next most abundant tree was Ironwood in 20 quadrats in 1945 and 7 in 1946. Others were much less numerous, for example Blue-Beech had ‘many seedlings’ in five quadrats in 1945, Bitternut Hickory and White Birch only in one.
Counting seedlings had become easier by the 1970s with an illustrated guide (Brayshaw 1959). Summed numbers from all sampled quadrats were Sugar Maple 16,713, Ironwood 868, White Ash 667, American Basswood 641, Red Maple 393, Bitternut Hickory 183, Black Cherry 70 and all others less. Nineteen seventy-seven appears to have been a mast year for Sugar Maple, with a single quadrat containing 6,982 seedlings. Sugar Maple was also most widely distributed, found in 60% of quadrats, Bitternut Hickory was in 42%, Ironwood in 40%. High densities of Sugar Maple and Ironwood seedlings did not always co-occur.
Percentage frequency of all sizes of trees in the 1970s is shown in Table 1, Column E (n=2121). Sugar Maple was followed by Ironwood, White Birch, Largetooth Aspen, White Ash, American Basswood, Eastern White Cedar and Black Cherry. White Elm had disappeared since the 1940s, while Black Locust, Red Pine, Balsam Poplar, Eastern Cottonwood, Red Ash and Yellow Birch were now found. The difference in area sampled including quadrats at Cow Island Marsh can account for an apparent decrease in Eastern White Cedar, Speckled Alder and Corylus sp., but probably not for American Basswood. The greater frequency of Sugar Maple and Ironwood has been accompanied by an increase in pioneer species such as the aspens and cherries. The ashes offer an anomaly; in the 1940s Black Ash and White Ash were reported in equal numbers, but in the 1970s White Ash had greatly increased, Black Ash had disappeared, and Red Ash was well represented. It is possible that the ashes may have been misidentified in the earlier surveys, but since Black Ash is the only local species in which the leaflets are not stalked it seems very unlikely. Another possibility is that the wet habitat of the Black Ash dried out during the thirty years however we have no evidence to support this idea. Another anomaly was the decision of the 1940s crew to include counts of one shrub, Common Juniper. Obviously it was a noticeable feature of the old fields, but why not count all shrubs? In addition to the junipers Crataegus sp., Staghorn Sumac, Amelanchier sp, Salix sp. and Choke Cherry were mentioned. Both Pin and Choke Cherry were abundant in the 1970s.
Acknowledgements
The two notebooks will in future be kept in the library at QUBS. Our thanks go to Ted Brown, Floyd Connor, Frank Phelan, Dale Kristensen, the staff of the map Library in Stauffer Library for their help, Fiona Munro and Cally Toong at QUBS for cleaning up maps and helping with historic photo records, Paul Grogan for taking care of the notebooks, and of course the students who counted seedlings and trees in both decades. Particular thanks are due to those who counted the 6982 sugar maple seedlings in one quadrat! It would be excellent if one or more of the recorders of the 1940s identified themselves as a result of this blog. We are happy to have been able to have read this article to Ted Brown before his recent death.
References
Brayshaw, T.C 1959. Tree seedlings of Eastern Canada. Bull.122 Dept. Of Northern Affairs and Natural Resources. Forestry B ranch.
Crowder, A. and R. Harmsen. 1998. Notes on Forest Succession in Old Fields in Southeastern Ontario: the Woody Species. Canadian Field-Naturalist 112(3) : 410-418.
Farrar, J.L. 2009. Trees in Canada. Fitzhenry and Whiteside Ltd and the Canadian foret Service. Markham, Ontario.
Nicholson, W.L. and L. M. Sebert. 1981 The maps of Canada. Wm. Dawson and Sons Ltd. Folkestone, U.K.
Robertson, R. Biology faculty reminisce-careers in perspective:focus on Drs. Adele Crowder and Ted Brown. Queens’s Biology. Autumn 2008. Vol.3 :4-6.
Smallman, B.N., H.M. Good and A.S. West. 1991. Queen’s Biology, an academic history of innocence lost and fame gained 1858-1965. Department of Biology, Queen’s University at Kingston.
Tansley, A.G., and T.F. Chipps, (eds). 1926. Aims and Methods in the Study of vegetation. The British Empire Vegetation Committee. London.
J.H. White 1946 The Forest Trees of Ontario and the more commonly planted foreign trees. First Edition 1925. Ministry of Natural Resources. Ontario.
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