Japanese Stilt Grass

Microstegium vimineum ( Japanese Stiltgrass )
An annual weed reaching a maximum height of 3.5 feet through often much shorter ( especially in cut lawns ). It is native to far eastern Russia and Japan; south to India and Indonesia. It is one of the worlds most invasive plants with potential to disrupt entire ecosystems in North America where natural controls are not present. Woodland edge and floodplain forests are most at risk of ecosystem disruption due to stiltgrass. Deer predation in gardens and remaining native plants has increased considerably in areas where Stiltgrass and Wavyleaf Basketgrass has taken over native ecosystems. Both Japanese Stiltgrass and Wavyleaf Basketgrass are not edible to deer. Japanese Stiltgrass has been detrimental to many species of ground nesting birds that utilize the woodland floor, such as Bobwhite Quail. In its natural range in southeastern Asia, Wavyleaf Basketgrass is a food source for many species of Lepidoptera, including Elachista kurokoi. The Elachista kurokoi Moth is a voracious feeder on both Wavyleaf Basketgrass and Japanese Stilt Grass...THIS MOTH MUST BE INTRODUCED TO NORTH AMERICA TO SAVE OUR ECOSYSTEMS!!! The larvae of the Elachista kurokoi moth mine the leaves of their host plant which can be both Japanese Stiltgrass and Wavyleaf Basketgrass. The species survives the winter in the pupal stage. There are many species of Elachista Moth, each species of these grass-miner moths have specific grass preference. Elachista kurokoi would therefore by unlikely to have any appetite for grasses native to North America. It is a pretty but very small moth, often only 0.1 inches long, that is black with white ( usually 3 wing bands ). Recommended photo link of the Elachista kurokoi Moth ( https://www.inaturalist.org/taxa/416471-Elachista-kurokoi ). Biological controls have been safe and successful for the control of Purple Loosetrife which during the 1980s had overtaken and rendered ecologically worthless many wetlands in Ontario, Canada and surrounding U.S. states.
( www.dnr.state.mn.us/invasives/aquaticplants/purpleloosestrife/biocontrol.html
( https://bugwoodcloud.org/resource/files/6225.pdf ). In Ontario, Canada; biological controls through the use of predatory beetles has resulted in some Purple Loosetrife infestations declining by up tp 90% biomass in a single season. ( http://www.ontarioinvasiveplants.ca/wp-content/uploads/2016/07/Purple-Loosestrife-BMP-April-2016-final.pdf ).
Japanese Stilt Grass is likely now here permanently in North America, however the main purpose of biological controls would be to sharply reduce its abundance to be as benign as the common dandilion which has relative insignificance in regards to ecosystem disruption. According to the The Mid-Atlantic Invasive Plant Council, there are 2 species of a plant disease called Bipolaris which can cause leaf spot on and kill Japanese Stilt Grass. This is also a promising natural control. Bipolaris microstegii has been reported to cause severe leaf blight and dieback on stiltgrass around Frederick, Maryland. It has more recently been found in nearby Howard County. Bipolaris first shows up during early summer as dark lesions on stiltgrass leaves, a few weeks later the entire plants will turn brown, dry up and die. Bipolaris first showed up in North America on stiltgrass in West Virginia in 2008 and does not seem to affect any native grasses or other plants. During August 2012 Bipolaris microstegii was observed in Maryland for the first time on Indian Springs Road in Frederick, MD
Recommended links
( https://environment.arlingtonva.us/2015/11/update-on-biocontrols-for-invasive-plants/ )
https://www.researchgate.net/publication/316531817_Differential_Aggressiveness_of_Bipolaris_microstegii_and_B_drechsleri_on_Japanese_Stiltgrass )
. Japanese Stilt Grass is thought to have been accidently introduced into the U.S. through its use as a packing material for porcelain products from China. The seeds can survive in the soil for up to 5 years years and generally germinate during mid to late spring ( around the same time as crabgrass ) however many seeds continue to germinate all summer long, making control from flower beds virtually impossible. A single stilt grass plant can produce up to 1000 seeds. Floods often enhance the spread of Japanese Stilt Grass in floodplain forests, the seeds themselves can survive up to 10 weeks submerged in water. Once established in a neighborhood, eradication without biological controls becomes impossible. In neighborhoods with severe stilt grass infestations, most desirable turf grass gets invaded and eventually destroyed. Statistics for effects of Japanese Stiltgrass on livestock pastures and food crops are not available. Some grasses are known to produce an allopathic soil toxin similar to the most famous one Juglone found near Black Walnut trees, research is inconclusive on the effect of compounds from Japanese Stilt Grass supressing the growth of nearby trees though from personal observations I consider it likely and significant. Studies like this would be difficult as growth suppression on nearby desirable plants would also come from the Stilt Grasses effects of robbing vital nutrients as well as precious water during times of drought.
The lance-shaped leaf blades are up to 4 x 0.6 inches in size. The foliage is bright green.
The seed spikes, up to 2.8 inches long, ripen during early to mid autumn. It is a prolific reproducer and removal of plants whether by hand pulling or line trimming is recommended to control spread.
Hardy zones 4 to 9 in partial to full shade ( full sun on moist soils ).

* photos taken on Aug 11 2015 in Columbia, MD

* lawn infestation taken on Aug 11 2015 in Columbia, MD

* photos taken on Sep 19 2015 in Columbia, MD

* photos taken on Aug 12 2016 in Howard Co., MD

* photos taken on Oct 31 2018 @ Howard Comm College, Columbia, MD

* photo taken on June 13 2019 in Ellicott City, MD

* photo taken on June 26 2019 @ Howard Comm. College, Columbia, MD

* photos taken on Aug 24 2019 in Columbia, MD

* photos taken on Sep 10 2019 in Columbia, MD

* photo taken on Oct 22 2019 in Columbia, MD

* bipolaris fungus infected stiltgrass in lawn

Oplismenus hirtellus ssp. undulatifolius ( Wavyleaf Basketgrass )
A perennial weed, reaching up to 2 feet in height, that is native to woodland from northern India to southeastern China as well as Japan. It has recently become established in parts of the eastern U.S., especially in Maryland and northern Virginia, where it has become a noxious weed causing severe damage to forest ecosystems. It can also take over sites in full sun as long as the soil is consistently moist. Deer predation on gardens and remaining native plants has increased considerably in areas where Wavyleaf Basketgrass has taken over native ecosystems. Wavyleaf Basketgrass is not edible to deer. There has not been much research in North America on biological controls yet, however it appears that wavy-edged basketgrass in Columbia, Maryland is infected by the same fungus ( bipolaris microstegii ) that effects Japanese Stilt Grass and is already declining in places locally. Forests, shorelines and grasslands invaded by Wavyleaf Basketgrass often end up becoming biological dead zones. Natural reproduction of trees in forests invaded by Wavyleaf Basketgrass does not occur. There is strong concern that Wavyleaf Basketgrass will disrupt and destroy ecosystems throughout the Mid Atlantic and southeast if the current infestations in Maryland and Virginia aren't checked. Besides being an extremely prolific reproducer by seed, it can also spread laterally by stolons which can reach several feet in length. The seeds readily stick to passing animals and humans clothes and readily disperse. Yard waste recycling programs also spread this noxious weed through the further use of non-sterilized mulch and compost. It is thought that the wavyleaf basketgrass invasion in the U.S. began by the discarding of hanging baskets imported from China within the state of Maryland. In its natural range in southeastern Asia, Wavyleaf Basketgrass is a food source for many species of Lepidoptera, including Elachista kurokoi. The Elachista kurokoi Moth is a voracious feeder on both Wavyleaf Basketgrass and Japanese Stilt Grass...THIS MOTH MUST BE INTRODUCED TO NORTH AMERICA TO SAVE OUR ECOSYSTEMS!!! The larvae of the Elachista kurokoi moth mine the leaves of their host plant. The only other plant they are known to feed on other than the above is Digitaria timorensis which is not known to occur in North America.
Further article published by U.S. National Early Detection and Rapid Response System for Invasive Plants ( http://nc-ipc.weebly.com/uploads/6/8/4/6/6846349/wavyleaf_basketgrass.pdf )
Link on wikipedia ( https://en.wikipedia.org/wiki/Oplismenus_undulatifolius )
The lance-shaped leaf blades are up to 6 x 1.2 inches in size.
The seed spikelets ripen late summer to mid-autumn.
Hardy at least north to zone 7 in partial to full shade ( also full sun on moist soil ).

* photos taken on Sep 19 2015 in Columbia, MD

* photos taken on Aug 13 2016 in Reisterstown, MD

* taken July 12 2020...basketgrass with disease ( possibly bipolaris microstegii )