Of course, we can expect some fruit reduction in cases where
severe frost or freezing catches trees in the stages of tender
bloom and early fruit set. Book figures are about a 10 percent
reduction in apples at full bloom with a temperature of 28
degrees. Peaches and apricots in early fruit set at similar
temperatures will see about a 25 percent fruit reduction. An
additional decrease in temperature to about 26 degrees magnifies
the losses. Of course this isn't always bad. Many have been
complaining the past couple of years about too much fruit and
Of bigger concern is rhubarb. A hard freeze
can actually damage leaf cells enough to release a toxin back
into the leaf stalks. The leaves are always toxic on rhubarb,
and if damaged enough to wilt or have black or brown along the
edges, the toxin is almost certainly released. The solution is
rather simple, at least this early in the game. Pull the stalks
with the damaged leaves, and you get to start over with the
regrowth. It may happen again as the plants have more growth,
but at least now we are early enough we don't feel quite so bad
about starting at ground level again.
For those who got some potatoes set out, if foliage is
damaged enough to wilt, it is probably best to cut tops back to
ground level and allow regrowth. Rotting back into the tubers
causes more problems later on.
Garlic mustard is a cool-season biennial herb with stalked,
triangular to heart-shaped, coarsely toothed leaves that give
off an odor of garlic when crushed. First-year plants appear as
a rosette of green leaves close to the ground. Rosettes remain
green through the winter and develop into mature flowering
plants the following spring. Flowering plants of garlic mustard
reach from 2 to 3 1/2 feet in height and produce buttonlike
clusters of small white flowers, each with four petals in the
shape of a cross. We haven't reached the temperature threshold
for the flower stalks to elongate, but that will come shortly.
Control of garlic mustard is somewhat difficult. Seeds can
remain viable for at least five years in the soil. Small amounts
can be pulled up (including the roots). Garlic mustard can
regrow from root material.
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For herbicides, glyphosate (Roundup) is the most often recommended.
Remember, glyphosate kills broadleaves and grasses when it gets on
them. There has been some success with 2,4-D LV400 where there
aren't concerns with other understory plants.
Very large patches have been controlled with fire, but that
completely destroys the understory of timbers.
Remember to monitor garlic mustard areas for at least five years
due to the seed dormancy period. Some action at this early time may
help prevent larger problems down the road. It is much easier to
control small patches than large ones.
The to-do list
Get ready to mow!
Many are actually looking forward to the mowing duties after the
winter we've experienced. Use a mower with sharp blades, and
remove no more than one-third of the leaf blade — for a 2-inch
mowing height, mow when grass is 3 inches tall.
Roses should have
their final pruning any time now. It appears winter damage was
severe on the Knock Out roses I've looked at. Cut back to green
wood — hopefully you have some left!
Plant early garden now, if you haven't
already. This would include things such as lettuce, spinach,
onions from sets and other items that tolerate frosts. Hold off
on those warm-loving plants such as tomatoes until after May 10.
University of Illinois
Extension director for Logan, Menard and Sangamon counties]