A member of the chicory tribe, along with lettuce, dandelions, endives and radicchio, so not surprising you can use it in salads. Youngia thunbergiana is very similar to Y. japonica (RBD #508) but you can tell them apart by looking at the leaves.[doi:10.2179/13-018] Both are native to east Asia.
2023-04-15 C&O Canal, Potomac, MD
Arthropod jujitsu: Use plant defence for food and shelter. The technique has been invented many times in mites, flies, wasps, beetles, bugs, thrips and moths, each triggering a defensive response in its own way.[doi:10.3390/d11100180] In this case a gall midge (Acericecis ocellaris) specific to red maple (Acer rubrum) releases a hormone that induces the colour change.* After feeding for a few weeks it'll drop to the soil to pupate and overwinter.
2023-04-29 Rock Creek Park, Washington DC
* I was unable to find further details. I wonder if it is triggering the usual fall leaf cycle where nutrients are released from the leaf cells then stolen by the larva?
Hanging on, but how? Apparently, using a dry adhesive mechanism similar to geckos.[*doi:10.1242/jeb.061507] Each leg ends in adhesive pads packed with tiny flexible "spatulas". These bend to conform to the surface, maximizing contact area and making them stick (suction? van der Waals forces?). This fails on surfaces with fine grained roughness, reducing contact area to just the surface peaks.
2023-04-29 Rock Creek Park, Washington DC
* Lots of pretty images in this paper, though for Philodromus dispar whereas this photo shows P. rufus or similar.
"Dimorphic" because males are split into two morphs so distinct they were once thought to belong to different species.[doi:10.1073/pnas.90.24.11954] Females will mate with either form, but only if he shows all the right moves. The brighter tufted morph starts his dance standing tall and far away, with legs waving above his head, but the muted gray morph crouches nearby and sidles side to side. Somehow these distinct body patterns and dance moves are stored and coordinated in the DNA, with the female producing equal numbers of each no matter which male morph she selects. If the guy uses the wrong dance form he will be rejected.*
2023-04-29 Rock Creek Park, Washington, DC
* Some grad student spent their research years making computer anime of Maevia inclemens mating dances to test female preference. It's not porn, it's erotica.
Ajuga reptans: A low maintenance shade-loving ground-cover from the mint family.[1] But this is a palearctic plant (hailing from the old world), so these wonderful qualities are considered bad. Looking at iNaturist observations, it is equally comfortable in Europe, North America and New Zealand.
2023-04-15 Bethesda, MD
[1] North Carolina Plant Toolbox, North Carolina State University Extension. (Website)
Classic carrot family, with its umbrella-like flowerhead (called a compound umbel, after Latin umbella* for parasol). Zizia aurea is a keystone species providing early season nectar for many different bee families.[doi:10.1371/journal.pone.0240354] They should be included in "prairie strips". stretches of flowers and grasses planted beside crop fields as refuge for native insects and plants. Corn and soy, which together consume 170 million acres of crop land, do not provide nectar.
2023-04-16 Bethesda, MD
* From a 1st century epigram for parasols entitled Umbella (umbra+-la, or "little shadow"). I wonder if some ancient scribe dropped an "r" when hand-copying text? The word for umbrella, umbraculum (umbra+-culum, also "little shadow"), is much more common in ancient texts.
The garden tulip (Tulipa gesneriana) is likely derived from the Duc van Thol tulip (T. suaveolens) native to the southern Steppe (Crimea to Kazakhstan).[1] This is a young species with a broad range of colour and shape. The variation is likely due to climate, with the red pigment protecting the plant from drought and heat stress.[2] Colour can be further affected by disease, such as the tulip mosaic virus, which forms stripes on the petals.[3] These variations were highly prized during the 1600s, but they were hard to control. Modern cultivars produce consistent striping without the aid of viruses.
2023-04-15 Bethesda, MD
[1] doi:10.1007/s00606-020-01667-7 [2] doi:10.1134/S1062359022100259 [3] doi:10.1094/PDIS.2000.84.10.1052
A native ground cover for full shade, Tiarella cordifolia has pretty white flowers in spring and interesting leaves that stay green all year. (They had me at "full shade"!) It thrives in the dappled light of east coast forests, using the brief periods in spring and fall when light levels were 10x to 100x higher to gain most of its biomass.[doi:10.1046/j.0269-8463.2001.00584.x] Astringent leaves, so the deer and the rabbits mostly leave it alone.
2023-04-15 Bethesda, MD
Pulsatilla alpina is yet another member of the buttercup family, this from the anemone tribe. It, too, is toxic, yet still has to play host to parasites. For example, Phytomyza pulsatillae, a leaf-miner fly whose larvae leave winding tracks under the surface as they feed. Sheep avoid the plants because they don't like mouth blisters, giving the flies a safe place to grow.
2023-07-10 Les Karellis, Savoie, FR
Another Asian ornamental, Clematis terniflora is much more aggressive, spreading along forest edges and smothering native plants. Still pretty even when it has gone to seed. It has widespread use in Chinese medicine for rheumatoid arthritis and prostatitis. Still, it is disturbing to read animal studies with phrases like "writhing test" and "sensitivity of the scrotum to heat and pressure" (clematis helps, but not as much as aspirin).
2023-11-12 C&O Canal Lock 7, Potomac, MD
It is always a challenge to decide what to include in a post. Do I mention the woman who put mashed clematis leaves on a tick bite, then spent several days in hospital dealing with second degree burns? This is probably related to the protoanemonin, which is nasty when fresh, but quickly degrades to the point where farmers have been known to feed dried clematis to cows. What about the report on wild capuchin monkeys from Costa Rica, which rub various medicinal plants into their fur, including a species of clematis (though not C. terniflora)?
Another buttercup family member, Clematis montana is an Asian ornamental. Highly toxic but fatalities are rare because of intense bitterness and mouth irritation (I'll trust this daim without verifying ;-) Curiously, the primary toxin acts as an antimutagen: an E. coli strain known to mutate under UV has a tenth the number of mutant cells when grown in agar inoculated with protoanemonin. [DOI:10.1016/0165-1218(83)90069-1]
2023-04-15 Bethesda, MD
Buttercup family(!?), with an evolutionary codependence on hummingbirds and other long-tongued pollinators. At some point Aquilegia added code to make their cells long and skinny, allowing individual species to adapt to different pollinator preferences.[1] This red columbine (A. canadensis) has relatively short spurs (2.6 cm), providing nectar for the ruby-throated hummingbird, whose fast-beating wings blow pollen between the plants while it feeds.[2] By contrast, the longspur columbine (A. longissima) with its 15.9 cm spurs needs the rustic sphinx (Manduca rustica) with its 14 cm tongue. Carpenter bees skip the evolutionary challenge and cut through the tube walls to steal the nectar, so columbines need self-fertilization as a backup.[3]
2023-04-15 Bethesda, MD
[1] DOI:10.1098/rspb.2011.1873 [2] DOI:10.2307/2465304 [3] DOI:10.2307/2656717
A variety of common blue violet (Viola sororia f. priceana) named for the colour of its flowers. V. sororia flowers in spring, producings seeds by cross-pollination while providing food for various bees and butterflies. The seeds have a tasty coating of proteins and lipids, providing food for ants. The ants carry the seed to their nest, eat the coating, then toss the kernel into their midden where it can germinate. In late summer violets self-pollinate without bothering to flower, then hurl the seed up to 270 cm away for germination. Much cheaper since they don't have to pay for pollination and transport, but without the benefits of sex and targeted delivery to fertile soil.
2023-04-16 Bethesda, MD
Note: iNat lists 44 species of violet in Maryland, 10 white, 5 yellow and 29, well, violet.
The history of hybrid ornamentals is surprisingly recent. The first controlled experiment was in 1716 when Thomas Fairchild[1] used a feather to transfer pollen from a Sweet William (Dianthus baratus) to a Carnation (D. caryophyllus) to produce the sterile "Fairchild's Mule". A century later, the garden pansy was born (Viola x wittrockiana).[2] Unlike most violets, the wild pansy (Viola tricolor) branches above ground to produce many blooms. This was crossed with mountain pansy (V. lutea) and a Siberian species (V. altaica?) to produce a large-bloomed flower with blocks of colour. The flowers can be used in salads and desserts, with nutritional value is akin to romaine lettuce and flavour similarly subtle (i.e., bland).[3,4]
2023-04-15 Bethesda, MD
[1] Thomas Fairchild (gardener): Wikipedia
[2] Pansies: Aggie Horticultural (website), Texas A&M
[3] DOI:10.1016/j.foodchem.2018.01.102
[4] DOI:10.5539/jas.v8n11pxx
Introduced to the Americas as an ornamental ground cover,* Vinca major readily spreads in a variety of light and soil conditions with zero maintenance, giving a pretty display every spring. Along with the price (75 cents/plant in bulk) this makes it popular with landscapers. Of course, the plant doesn't care about property lines, as you can see when walking through the local forests.
2023-04-15 Bethesda, MD
* Periwinkle has been used by herbalists in Britain since at least the 15th century,[1] but curiously it does not appear in a comprehensive guide to medicinal plants from the US in the 1850s.[2]
[1] Grieve M. (1931) A Modern Herbal (website)
[2] King, J., and Newton, R.S. (1852) The eclectic dispensatory of the United States of America. HW Derby & Company.
A garden-variety blueberry (it is, afterall, growing in our garden), this is a native cultivar we bought without much consideration some 20 years ago. Probably Vaccinium corymbosum. It hasn't been a great success. If I put a net over the bush I can get enough berries to fill a punnet, but most years the birds get there first.* That's good for the birds. Lots of antioxidants and vitamin C. And medicinal: both berries and leaves inhibit MRSA.[1] Blueberries are sometimes added to pemmican**, presumably for flavour, but also as a preservative. The antioxidants keep the fats from going rancid.[2]
2023-04-16 Bethesda, MD
* Mister McGregor deserves some sympathy.
** Pemmican: powdered dried meat and berries mixed with equal parts lard and kept unrefrigerated for a year or more. No salt in the traditional recipe.
[1] DOI:10.1016/j.foodcont.2014.11.040 [2] DOI:10.1016/j.meatsci.2021.108526
If you can't handle the heat then don't live downstream from a hot spring. A dozen species of moss have been found growing near 80 °C springs in Iceland.[1] Growing practically everywhere, B. argenteum can be used to monitor the environment, picking up metals such as iron, lead and zinc from contaminated air and soil.[2]
2023-05-19 Reykjadalur, Iceland
[1] Elmarsdóttir, Ásrún, Olga K. Vilmundardóttir, and Sigurdur H. Magnússon. Vegetation of high-temperature geothermal areas in Iceland. Proceedings of the World Geothermal Congress. 2015.
[2] Aceto, Maurizio, et al. (2003). The use of mosses as environmental metal pollution indicators. Chemosphere 50(3) 333-342.
Iceland had lots of tide pools, but not so much activity this early in the season. We did spot this group of periwinkles grazing on algae near black mussels. Or maybe it is a group of dog whelks grazing on the mussels. Both species are highly variable, but periwinkles generally have fewer, deeper whorls. About a million pounds of periwinkle are harvested in Maine each year, leaving a whole lot of shells behind. These can be ground to a fine powder, mixed with resin and used as brake pads.[1] Unlike other alternative brake materials (sugarcane husks, palm kernel shells), these do not swell in water or oil, while having performance on par with banned asbestos-based pads.
2023-05-14 Hafnarberg Seacliffs, Iceland
[1] DOI:10.1016/j.jksues.2013.11.002
Today's oxymoron: crystalline fluid. Deep inside the glacier the pressure from above coaxes ice to form large hexagonal sheets, like the graphite in a soft pencil. The bonds between the sheets continually break and reform, allowing the glacier to flow down hill. Near the surface, though, with much less pressure the ice is brittle, forming cracks where it bends. These cracks let in surface melt water, which worms its way through the glacier carving out a network of tunnels. The large volume of rapidly flowing water forms a series of eddies along the tunnel walls, scalloping the surface for our enjoyment.[2]
2023-05-16 Katla Ice Caves, Vik, Iceland
[1] DOI:10.3189/002214311796406185 [2] DOI:10.1017/jfm.2019.398
This mountain of ice is the tip of Kötlujökull, one of the outlet glaciers draining the Mýrdalsjökull ice field. The black layers contain ash fall from various volcanic eruptions, squeezed between layers of ice. Underneath the ice cap lies the Katla caldera, which has erupted about every 45 years since settlement began. When it does, the hot magma melts the ice causing a surge of water to flow down the valley. The 1918 eruption dumped about 2 billion cubic meters of sediment onto the floodplain, extending the coastline by hundreds of meters over several kilometers.[DOI:10.1002/2014gl060090]
2023-05-16 Katla Ice Caves, Vik, Iceland
Part of a nutritional breakfast, the leaves of Salix lanata have a higher concentration of minerals than the usual grass fodder (N, P, K, Ca, Mg).[1] Willow and birch leaves have been part of the diet of Icelandic flocks for hundreds of years. A little harder to digest with their excess lignin, but still heavily browsed by sheep. Farmers would collect leaves for winter especially in years when grass was sparse.
2023-05-17 Stjórnarfoss, Kirkjubæjarklaustur, Iceland
[1] DOI:10.1111/gfs.12224