[Maipc] Q's about garlic mustard: size of plants and possibly adisease
Irene O. Sabin
iosabin at earthlink.net
Mon Apr 16 15:33:52 PDT 2012
This is some research that I did on garlic mustard:
"In the USA, garlic mustard is typically a biennial. It takes two years to
fully mature and set seed. In the first year, the plant forms a low cluster
of leaves (basal rosette) and spends the winter in that form. It matures
rapidly in the second year, produces flower stalks, sets seed, and then
dies. Mature plants can reach a height of 3.5 feet in good growing
conditions but flowers can also appear on much shorter stems. Flowers can be
self-pollinated or cross-pollinated by insects. Because it is self-fertile,
a single plant can populate or repopulate an entire site.
Garlic mustard reproduces only by seeds. Depending on geographic location,
mature seeds may remain dormant for 8 to 22 months and require 50 to 105
days of cold stratification (exposure to a range of low temperatures) in
order to break dormancy. Seeds usually germinate as soon as dormancy is
broken but seed populations may remain viable in the soil for at least five
years. The average single plant produces 600 seeds to over 7500 seeds for a
very vigorous, multi-stemmed plant. Soil disturbance aids in seed
production so reproduction is highest in the most disturbed sites. The size
of mature garlic mustard populations on a site can vary from year to year
depending on when seeds germinate."
I'm not sure how crinkled the leaves are on your plants but the leaves
change in shape from fairly round basal rosette leaves to smaller heart or
wedge shaped leaves as they grow up the stem to the top. The top leaves have
fairly deep "teeth" around the edges. You will need to monitor your area for
5 to 7 years because seeds can remain in the ground for that length of time.
When you pull the plants, bag all parts and dispose of the bag in the trash
(do not compost). Tops of roots can grow new plants, flowers continue to
mature and the seed pods remain viable for a long time.
I hope this helps.
Irene Sabin (Rutgers volunteer) iosabin at earthlink.net
----- Original Message -----
From: "Ruth Douglas" <cvilleruth at embarqmail.com>
To: <maipc at lists.maipc.org>
Sent: Monday, April 16, 2012 6:02 PM
Subject: [Maipc] Q's about garlic mustard: size of plants and possibly
>I just got in from pulling all visible garlic mustard on my property. I
> about an acre of land in Albemarle Co., VA, not far from the city of
> Charlottesville. Much of my land is wooded.
> Last year I discovered to my horror that a patch of land, which is
> from my house and usually not visible to me unless I walk down to it, had
> fair number of gm stems, oh, maybe 200 or more. This year there is
> less, but I am trying to figure out why I found such a range of sizes
> the stems I pulled. Some are 6", some 12-18" and some up to 3 1/2 ' with
> multiple stems, and a wide range of root sizes. Why would I have such a
> range of size classes when I pulled virtually all of it last year (all I
> could spot) before the seed pods were dry. I thought they were "winter
> annuals" or biennials. If that is the case, why would there be so many
> sizes? (I realize this is a bit esoteric, but I am really curious). And, I
> do know that there is a seed bank.
> Then, some of the plants, maybe 5% or so had upper leaves that were
> "crinkled" and smaller and darker in color than usual. That makes me think
> there is some sort of disease that they are getting. I can't see anything
> obvious on the leaves such as fungi or insects. I have a dissecting
> microscope and have saved a couple of the crinkled leaf stems.
> Any help would be appreciated.
> Ruth Douglas
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