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three seeded mercury weed

From our Native Plant Image Gallery:

Creeping buttercups in juniper in McKeesport PA
May 22, 2010 – I have creeping buttercups in my juniper ground cover. How do I get rid of them.
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The first thing to do is make sure it never has an opportunity to go to seed. Even though it is a perennial that can come up from the roots, it will also propagate itself by the seeds on those tall bracts. This might be a time to break your rule about never mowing; if you mow it before it can seed, and keep mowing it as it sends up more bracts to try to seed again, you might just wear out the food stored in the roots. Doing this for several weeks when the plant is trying to bloom, and thus set seed, could greatly alleviate your problem.


More on oak problems in Carrollton TX
April 04, 2011 – Thank you for answering me, I will contact a specialist to see if we can determine the cause. but since writing you we have pulled down a small twig to see the leaf more closely, it is more of a reddi.
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Identity of invasive vine in The Woodlands, Texas
December 02, 2013 – What is the invasive vine covering trees in The Woodlands, Texas?
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Brown, dry leaves on weeping willow tree
May 01, 2008 – We live in central TX and have just planted a weeping willow tree. Our back yard has a retention pond and ravine that parallels our property and we were told that the weeping willow will do perfectly .
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Eliminating smartweed from pasture in Oswego NY
August 28, 2009 – How do I get rid of smartweed in my pasture?
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Photos and Pictures

General Description: Annual, reproducing only by seed.

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Stems & Roots: Stems erect, 7.5-100cm (3-40in.) high, simple or branched, slightly hairy; leaves green to bronze-green, 1-9cm (2/5-3½in.) long, lance- to rhombic-ovate on petioles that are 1/3 the length to almost as long as the leaf blade; margins with irregular, rounded teeth.

Flowers & Fruit: Flowers in greenish clusters in axils of leaves, each cluster composed of one or more palmately cleft bracts with 5 to 9 lobes, one or more stalked male spikes 4-15mm (1/6-2/5in.) long and one or more shorter female flowers; seedpods deeply 3-lobed (similar to those of Leafy spurge) and containing 3 seeds; seeds tan coloured, 1.6-1.8mm (1/15in.) long. Flowers from July to September.

Habitat: Three-seeded mercury occurs in dry or moist soil in open woods, fields, waste places, ditches and roadsides throughout south-central Ontario.

Finally, I know who this fellow is, sort of. Acalypha…somebody, probably rhomboidea, commonly known as three-seeded mercury. He and his brothers are everywhere in my garden.

This annual member of the Euphorbiaceae family starts as a thin, erect reddish stem with narrow leaves, about an inch to an inch and a half long, arranged opposite along the stem. As it grows, it branches, and leaves are arranged alternately. Here is where my ignorance of botany is exposed:There appear to be small yellow flowers at the leaf axils, but those yellowish bits I see could be bracts, or technically it might be an inflorescence …anyway, if you care to read details about the plant’s structure, you can read the description from the University of Guelph extension, or the Wikipedia site. For me, right now, I know I’m fairly close to identifying the plant.

This summer annual weed is not a nuisance, except that there’s a lot of it in my garden. It doesn’t reseed aggressively like hairy bittercress and it’s not difficult to eradicate. Despite the taproot, the plants are easy to pull. They are also said to be browsed by deer (not if there are phlox and hosta to eat, they’re not).

According to the Southern Living Garden Problem Solver, which may or may not have misclassified this as Acalypha virginica (my plant definitely doesn’t look like the one shown by Illinois, many insects love to feed on the leaves. Thus, my sample, with its raggedy, chewn leaves should be pretty typical.

The seeds are supposed to be choice food for mourning doves, whom I would gladly welcome to my garden because I love their call. The buffet is open!