Right now chickweed stands out in yards because it is
quite abundant and has a lighter green color than grass and most
other weeds. It is even evident as grass is just beginning to
green up. There are two types: common chickweed and mouse-ear
chickweed. Henbit is easier to identify since it has purple
flowers and smells like mint.
As for control, that gets a bit easier. The straight 2,4-D
that is used on dandelions seems to act like a fertilizer for
chickweed and other problem weeds. It's a growth regulator, and
if it doesn't actually kill a weed, it does make it grow faster.
Combinations that contain 2,4-D, MCPP and dicamba are rated very
effective on chickweed, henbit, red sorrel, purslane, white
clover and others.
These combinations are sold under several different trade
names. You can find these at most hardware, discount, and lawn
and garden stores. Just check the label under active ingredients
and check for two long chemical names and dicamba. You can also
check to see that it says it will control chickweed and henbit.
Just remember the control time for most broadleaf weeds is
early May. This group of chemicals is effective in the 50-degree
range and up. It just takes a lot longer for control with very
As with any chemical control, read and follow label
instructions very carefully. These product labels will have some
cautions you should be aware of concerning injury to sensitive
plants. This is because dicamba can drift as a vapor for a few
weeks after you apply it if the weather gets hot and sunny.
Fairy rings, mushrooms and puffballs
Throughout the year I get several calls and samples brought in
dealing with puffballs or toadstools. Even this early in the season,
we have had calls about dark green grass in rings that kind of look
like a target pattern. These rings are called fairy rings, and they
frequently have puffballs or toadstools growing in the area.
Fairy rings are caused by a fungus in the soil. Actually there
are about 50 fungi that can cause fairy rings. These fungi feed on
decaying organic matter such as large roots from trees that were in
the area, or from buried lumber. The dark green circle part of the
equation comes from extra nitrogen that becomes available as the
organic matter is broken down by the fungus.
Some prevention will help keep the problem from occurring. Simply
removing stumps, large roots and not burying lumber help prevent
this type of problem.
As for a cure, fungicide drenches have been successful on a very
limited basis. One option is to mask the symptoms of the dark rings
by fertilizing the surrounding grass with a high-nitrogen fertilizer
to make that grass green also.
As for the puffballs, toadstools or mushrooms, they are part of
the same complex as fairy rings. They are part of the natural decay
process that helps break down large wood items in the ground. There
is no real control, so mowing them off or knocking them loose with a
garden rake is about the best thing going.
University of Illinois Extension]