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Michigan Gardener | June 2015 | MichiganGardener.com
Sand tickseed (Coreopsis lanceolata), left, and showy tick trefoil (Desmodium canadense), right. As intimated by the common names for these two plants, their seeds are designed to hitchhike on passing fur- or fabric-clad mammals.
Downy serviceberry (Amelanchier arborea). The early-ripening fruits of this small tree are especially favored by robins, thrushes and thrashers. They are also edible for human beings, tasting like a cross between a raspberry and a blueberry.
How plants move around Nature’s amazing seed dispersal strategies
One characteristic we tend to identify with mammals alike—generally have a territory plants, as opposed to animals, is their inabilthrough which they travel in their daily or seaity to get around very well. Once they’re rootsonal routine. Plants with edible fruits—included in a given spot, that’s about it for the rest of ing serviceberry (Amelanchier), viburnum, and their terrestrial existence. elderberry (Sambucus)—are targeted by both But is that really true? Well, yes, birds and mammals for food. There in the sense that a particular plant, is a hierarchy here: highly desironce rooted, is pretty much home able fruits—fruits that are high in for the duration. That doesn’t mean, calories, where starches have been however, that its progeny are simiconverted to sugars—are eaten first, larly “stuck.” In fact, plants have with less desirable fruit lingering evolved some pretty amazing stratfurther into the season. In fact, some egies to get their seeds out—often, fruits are only really edible after they but not exclusively, through intigo through a freeze—one example of mate relationships with their more how Mother Nature keeps the larder Cheryl M. mobile faunal contemporaries. full through most of the year. English Fruit-eating animals—birds and Some fruits are only edible for
Virgin’s bower (Clematis virginiana). Blooming slightly earlier than the well-known yet invasive ‘Sweet Autumn’ clematis, this native vine is a superb substitute that boasts even showier, more persistent seed heads. certain animals. Virginia creeper (Parthenocissus quinquefolia) contains oxalic acid, which is toxic for mammals (its crystalline structure irritates both the skin and the digestive tract) but causes no problem for birds, which feed on the fruit with impunity. If you’re looking for a deer-proof plant with terrific fall color, this one is the ticket. Nut-bearing plants subscribe to a similar
strategy. I have never seen a squirrel bury a nut where he finds it; rather, he takes the nut somewhere else to “plant” it, usually some obscure pile of leaves some yards away. Furthermore, squirrels can tell a good nut from a bad one—a nut that has aborted in its development or has been damaged by some kind continued on page 26