Substrate-associated plants
Sourwood (Oxydendrum arboreum) is a tree with alternate, entire leaves that are “egg-shaped” and taste sour when chewed. Notably, the leaf scars of these twigs only have one bundle scar. Deer are known to browse on sourwood twigs, and the sourwood we saw at Deep Woods was actually at the edge of a meadow that Dr. Joe Raczkowski calls “Deer Field,” which I believe is a name he’s gotten from the landowners based on their sitings. which is appropriate Forsyth notes that sourwood only occurs in areas with exposed or nearly exposed sandstone bedrock. This limits its range to unglaciated Ohio, as well as some localized areas along the line of glaciation with very thin till that exposes the sandstone underneath.
Chestnut oak (Quercus Montana) is an oak (alternate leaf arrangement) with relatively shallow lobes that may also be described as very coarse teeth. It is superficially similar to chinquapin oak in leaf shape, but chestnut oak has rounded teeth as opposed to chinquapin oak’s pointed teeth. Additionally, chestnut oak is restricted to more acidic soils while chinquapin oak prefers limey soils. As an oak, many chestnut oaks have “galls” which may harbor many types of insects, many of them of the order Hymenoptera which includes ants and (specifically, tiny parasitoid) wasps.
Vaccinium spp. includes blueberries, deerberries, and other shrubs. These shrubs have alternately arranged, simple leaves, but the margins (entire or serrate) can vary since there are many, many species within the genus. Forsyth describes huckleberry-blueberry species within the genus as those primarily found on acidic sites. Many Vaccinium species have fruits that are edible for animals and both edible and tasty for humans!
Ferns
Polypody is a genus of ferns with many species. These are pinnatifid, meaning the fronds are deeply dissected and *almost* pinnately compound but the dissections don’t quite reach to the leafstalk, leaving no bit of the leafstalk fully exposed without leaf attachment. Additionally, these ferns are monomorphic. This means that spores are produced on the undersides of normal-looking fronds.
Christmas fern (Polystichum acrostichoides) is another fern found above the cave at Deep Woods. It is pinnate, with the same meaning as we use for tree leaves meaning the frond is fully dissected into completely separated leaflets. These fronds, however, are hemidimorphic, meaning that each frond has a fertile and sterile section. For these, there is a sudden difference between the larger (sterile) leaflets and the smaller (fertile) leaflets with sporangia underneath.
Royal fern (Osmunda regalis) is also hemidimorphic. This was the largest fern we saw on our trip to Deep Woods, and it was within The fertile leaflets are near the end of the frond with sterile leaflets closer to the base of the plant. This species is tripinnate, meaning the fronds are fully dissected three times.
Appalachian gametophyte
Vittaria appalachiana, known commonly as the Appalachian gametophyte, is a unique fern species in terms of life cycle. Whereas most ferns spend most of their life cycle as a sporophyte (the frond, or leaf, that you see when you recognize something as a fern), the Appalachian gametophyte has NO known mature sporophyte form and instead lives entirely as a gametophyte.
The Appalachian gametophyte, therefore, reproduces asexually and does so via gemmae. These are relatively large (when compared to spores) cell clusters that separate from the plant and can grow into full clones of the parent. Due to their size, they cannot disperse as far as spores. Over short distances, it’s likely that wind, water, and/or animals are responsible for the movement of gemmae. Kimmerer and Young (1995) report that some bryophyte gemmae are even dispersed by slugs!
Multiple studies have shown that the Appalachian gametophyte should be able to live in certain areas based on substrate and microhabitat (by comparison to similar sites the fern does live in or via transplant studies), but it hasn’t colonized those areas. The studies have suggested that this is due to distance and the difficulty of long-distance dispersal. Since it has been shown to live in very similar sites, there are no growing conditions as reasons for its failure to colonize. It’s suggested that, based on the distribution across the Appalachians and with an isolated range in New York, sporophytes and spore-production in this species were likely lost around the ice age, at which point it lost its ability to expand its range in any significant ways.
The preliminary rejection of the hybrid theory of origin for the Appalachian gametophyte suggests that the species only dispersed into temperate North America from the tropics one time. This denies the idea that tropical species are supporting this one through long-distance spore dispersal. Since gemmae cannot reasonably have been responsible for such a large range, research suggests that the Appalachian gametophyte did have a functioning sporophyte at one point and reproduced via spores and long-distance dispersal.
Boo hiss!
Japanese stiltgrass (Microstegium vimineum) is an invasive grass species that thrives in moist, shady areas and can easily overtake the understory of woodlands. Invasions typically begin at disturbed sites without much competition and spread easily into established sites. The flowers of this species can self pollinate and they are prolific seeders, which makes early control (before bloom) critical for their control. Some control options include regular mowing to prevent seed production, dithiopyr and indaziflam for pre-emergence chemical control, and clethodim, fenoxaprop or sethoxydim for post-emergence control (NC State Extension).
Trees in Trouble
Butternut, or white walnut, (Juglans cinerea) is an increasingly uncommon tree species in the same genus as black walnut (Juglans nigra). This tree species is at risk largely due to the butternut canker, a fungal disease that doesn’t have a cure. They may also be susceptible to wood borers, nut weevils, and other harmful insects. Interestingly, the common grackle is known to feed on immature fruits of butternut trees and is considered a pest for its disruption of natural reproduction (NC State Extension).
The cankers come from the fungus Ophiognomonia clavigignenti-juglandacearum. These cankers girdle branches or stems that they infect and effectively cut off nutrition flow up and down the tree. Once a canker has started, it cannot be reversed. Infected branches can be pruned off to try and prevent the spread of fungal spores to other branches and, most importantly, the trunk, but rain may have already washed spores onto the stem where they can infiltrate at wounds, branch scars, and leaf scars (Wisconsin Horticulture Division of Extension).