I just realized it has been seven weeks since I did a Six on Saturday post. It’s getting trickier to find six things that I haven’t already talked about, so today I thought I’d showcase plants that I normally wouldn’t mention at all.
1. Japanese stiltgrass (Microstegium vimineum)
This stuff is the worst. It’s an annual grass with long, jointed stems that can root at the nodes to spread over flat ground or climb and sprawl to smother plants up to about two feet (70 cm) tall. Stiltgrass was apparently introduced into the U.S. about 100 years ago, when dry stems were used as packing material for porcelain shipments. Around here, it can cover large areas of moist open woodland, along creeks and roads, where it completely chokes out native wildflowers. Seeds can survive several years in the soil, so even very careful weeding appears totally ineffective the next spring. According to Nancy Goodwin of Montrose Garden, stiltgrass can be eliminated by thoroughly weeding the same area for five or six years without fail. Mowing has no effect, as shown by the very short stiltgrass that combines with crabgrass to form much of my lawn in late summer. The busy (or lazy) gardener’s approach that seems to work relatively well is to cover all flowerbeds with a couple of inches of hardwood mulch every few years. The mulch stops seeds from germinating and enriches the beds, but it must be renewed as it decays, or stiltgrass will return
2. Poison ivy (Toxicodendron radicans)
The berries of this native vine/shrub are important food for birds, so seedlings often sprout around the bird feeder and bird bath, or under trees where birds like to perch. For small seedlings, I wear disposable nitrile gloves to pull the plant and then peel off the glove to trap the seedling inside. For larger plants, I use glyphosate–that’s the only time I use glyphosate in the garden.
3. Creeping cucumber (Melothria pendula)
This native annual vine is, as its name suggests, a member of the Curcubitaceae (gourd family). The vines are annoying when they form an untidy tangle that smothers tall perennials. The fruit are apparently edible when green but are very effective laxatives when ripe and black. Birds and squirrels eat them and distribute the seed throughout my garden.
4. Mulberry weed, hairy crabweed (Fatoua villosa)
I think this Asian member of the Moraceae (fig and mulberry family) arrived in my garden via some potted plants from a local botanical garden. It is an annual in the garden but invades pots in the greenhouse year round. The foliage of this species closely resembles various members of the mint family (e.g. catnip, lemon balm), but the hairy flower clusters are distinctive.
5. Chamber bitter (Phyllanthus urinaria)
An Asian species that is now distributed widely in the southeastern U.S., chamber bitter produces many seeds in little capsules along the underside of the stems at leaf axils. Chamber bitter is a problem mainly in bare soil, such as in my vegetable garden, or where mulch has decayed.
6. Pokeweed (Phytolacca americana).
I have heard that this piedmont native is sometimes grown as an ornamental perennial in Europe. An 8-foot (2 m) tall specimen with shiny leaves, red stems, and dark purple, almost black berries is definitely impressive, but wildlife spread the seeds all over the place. Even small seedlings have a deep taproot that makes them difficult to completely remove, and like dandelions, they’ll return if you leave the taproot in the soil.
For more Six on Saturday, hopefully including plants that you’d actually like to grow, head over to The Propagator.