Monsters in
Your Yard
Garlic mustard flower stalks
Rosettes
Pods
Alternatively, dispose of
garlic mustard plants with
a professional yard waste
operation such as Granger that composts at temperatures hot
enough to kill the seeds. It’s good to still seal the bags, so seeds
don’t spread along the way. If you work in an infested area, brush
off the soles of your shoes before moving to clean areas to avoid
spreading seeds. Similarly, avoid mowing garlic mustard once it has
set seed (in toothpick-like pods at ends of stalks; photo above),
because mowing will disperse the seeds.
3) Should you leave yard waste to decompose in a natural
area? While unintentional, this turns out to be the biggest source
of invasive species entering our natural areas. Like wraiths,
Japanese knotweed stalks, garlic mustard and other weed seeds in
yard waste have a life of their own! Once they spread out (and our
parks and neighbors often don’t have enough manpower to control
the invaders already on their hands), they will come back to you in
bigger numbers! The excess decaying matter also stimulates the
growth of bacteria and algae in wetlands entering the lake. What
to do? Keep compost piles within your property boundaries and
away from wetlands. Monitor compost to make sure weeds aren’t
hatching and moving into the surrounding areas. Better yet, seal
invasive weeds in yard waste bags and work with a professional
yard waste company to hot-compost them. If you think of nature
when handling your yard waste, nature will thank you beautifully!
It’s the time of year for raking fall
leaves, bagging yard waste, and
preparing for Halloween monsters! Image c/o fanpop.com
Did you know that monsters also lurk in your garden?
1) Can you name a shrub-like reed that you can hack into
Frankenstein-like pieces by mowing or pruning, and each
piece will start a new plant? These little Frankensteins grow
into 6-12 foot monsters strong enough to break through the
foundations of your house and overwhelm our waterways and
lakeshore!
2) Many of our yards have a 1-3’ tall
flower that grows in almost any spot:
sunny or shady, wet or dry. Forming
dense colonies, this alien releases up to
128,000 seeds per square yard of soil, and
the seeds can sprout up to ten years later!
Folks think it’s a native, until this plant
floods their gardens and woods, drowning
all the trilliums and spring beauties in its
path... Can you name this beast?
3) What happens when you put yard
waste on the edge of your property or
in natural areas or wetlands? Does it
all decompose? If it does, is that good?
Check out what Michigan experts
have to say on the next pages!
Image c/o
commons.wikimedia.org
Answer 1) Frankensteins. There are two invasive plants like
this in our area! The plant that can grow from stalk or root
fragments and break through cement is Japanese knotweed (photo
below). It evolved to grow on lava, and was initially sold as an
ornamental plant. This plant is now prohibited in Michigan due to
the damage it causes to roads, buildings, and natural areas.
Mowing or cutting Japanese knotweed only stimulates the spread
of its massive roots. Fragments of the stems and roots dragged by
the mower will start knotweed plants in new spots. Unfortunately,
it is only controlled well by specialty herbicides that aren’t available
over the counter. If you think you have Japanese knotweed on
your land, send a close-up photo to KuhnL@msu.edu, and we’ll
help! Mid-Michigan Stewardship and Ingham County Parks lead a
regional Japanese knotweed control effort.
the seeds, stems, and root cuttings carried by the mower can start
new plants. For controlling Phragmites with herbicides, special
precautions are needed near wetlands, which recharge our drinking
water and are home to sensitive wildlife. If you see Phragmites on
your land, send a photo to KuhnL@msu.edu at Mid-Michigan
Stewardship), and we’ll help!
Phragmites
stalk
Phragmites
colony
Japanese knotweed
Phragmites (frag-might-ees, also called common reed; see photos
on next page) is the second Frankenstein, originally planted to
stabilize ditches before folks realized that it devours waterways,
wetlands, and lakeshores. Phragmites is a giant, dense, reed-like
grass, growing 8-12 feet tall with feathery seed heads, and a colony
can spread up to 60 feet per year. It is considered a threat by
MDNR, MDEQ, and MDOT, filling in habitat needed by wildlife,
undermining roads, and presenting a fire hazard because it burns
hot and fast. Its spread is also stimulated by mowing/cutting, since
2) Alien flowers in your garden. Garlic mustard (shown on the
next page) is the highly invasive biennial. Imported from Europe to
the East Coast as an herb, it had spread to Michigan by the 1950s.
Garlic mustard leafs out early and has a longer growing season than
our native wildflowers. It blooms in May-June and then seeds
profusely in July. Mustard plants produce chemicals that make
them distasteful to herbivores and insects and also taint the soil,
preventing nitrogen fixation by native plants. Garlic mustard
rosettes (late 1st year and early 2nd year plants) outside of wet areas
can be sprayed with RoundUp™ (or equivalent) in the late fall or
early spring (when temperatures are ≥45F). RoundUp™ shouldn’t
be used in wet areas because it’s toxic to frogs, salamanders, and
fish. Garlic mustard seeds are long-lasting and not killed by lowtemperature home composting. It’s best to tightly bag and dispose
of flower or seed-bearing plants in your trash, which is buried in a
landfill where the plants can’t grow. This is supported by invasive
species regulations (Michigan Compiled Law, section 324.11521).