Weeds and Invasives
What is the process for controlling phragmites?
In order to allow for indigenous wetland species to germinate and grow we seek to control the phragmites along coastal banks. To accomplish this the phragmites are treated with Rodeo, a glyphosate based product approved for use in wetland areas. During the late summer/early fall (before a hard frost) when the phragmites is in half to full bloom the stalks should be cut to approximately 18” and the cut end of the stalk will be treated with Rodeo. Two weeks after this treatment the phragmites should be mowed to allow sunlight to help the germination of native species. In the subsequent years follow-up treatments should occur to prevent a resurgence of the invasive phragmites.
What is Yellow Nutsedge and how can I control it in my lawn?
Yellow nutsedge, also known as yellow nutgrass, is a warm season perennial in the sedge family. Sedges look like grasses, but if you roll the stem of sedges between your fingers you will notice they are three sided. Grass stems are round or flattened. Yellow nutsedge is native to Illinois and many parts of North America, including New England.
Nutsedge is often considered troublesome when it appears in lawns. It is a lighter green and grows faster in hot weather than our lawn grass. Nutsedge has upright, light yellow-green leaves 1/8 to 1/2 inch wide and up to three feet long. They have parallel veins with a prominent midvein. Leaves grow rapidly in summer often appearing well above the lawn grass. Nutsedge has a fibrous root system. It also develops horizontal underground stems (rhizomes) with white tubers (nutlets) forming on the ends of the rhizomes.
Tubers develop rapidly six to eight weeks after the plants emerge usually during late July and August. Nutlets may get to be almost an inch in diameter. Unfortunately the nutlets may persist in the soil for many years. New plants emerge from the nutlets from late May to mid-July.
Yellow nutsedge is often an indicator of poor drainage. It particularly likes wet or moist sites or sites heavily irrigated. However it can grow in all soil types and can tolerate dry sites once it’s established. Yellow nutsedge is difficult to control especially once it has formed tubers. If you want to control it, don’t wait. Once it has formed tubers, pulling it out will only remove the original plant.
To control nutsedge without chemicals, maintain a thick stand of lawn grass through proper maintenance. A maintenance schedule is available throughthe University of Illinois Extension Offices. Pull nutsedge plants soon after emergence before nutlets can form. Modify drainage in moist or wet areas. Check for nutlets in purchased soil or mulch.
If herbicides are chosen as the control option, there are several available to be used in lawns once the nutsedge emerges. However herbicides often will not give total control and multiple applications may be necessary. Herbicides for nutsedge control are generally applied from mid-summer to mid-fall. Commercial turfgrass managers may use Basagran (bentazon) or herbicides containing MSMA. Home gardeners should look for herbicides specifically formulated for nutsedge control. Ortho as well as other companies make a crabgrass and nutgrass killer. Always read, understand and follow the label directions. ( Source: University of Illinois)
What is Japanese Knotweed?
Japanese Knotweed has hollow stems with distinct raised nodes that give it the appearance of bamboo, though it is not closely related. While stems may reach a maximum height of 3–4 m each growing season, it is typical to see much smaller plants in places where they sprout through cracks in the pavement or are repeatedly cut down. The leaves are broad oval with a truncated base, 7–14 cm long and 5–12 cm broad, with an entire margin. The flowers are small, creamy white, produced in erect racemes 6–15 cm long in late summer and early autumn.
In the U.S.A. and Europe, Japanese knotweed is widely considered an invasive species or weed. It is listed by the World Conservation Union as one of the world’s 100 worst invasive species. It is a frequent colonizer of temperate riparian ecosystems, roadsides and waste places. It forms thick, dense colonies that completely crowd out any other herbaceous species and is now considered one of the worst invasive exotics in parts of the eastern United States. The success of the species has been partially attributed to its tolerance of a very wide range of soil types, pH and salinity. Its rhizomes can survive temperatures of −35 °C (−30 °F) and can extend 7 metres (23 ft) horizontally and 3 metres (9.8 ft) deep, making removal by excavation extremely difficult. The plant is also resilient to cutting, vigorously re-sprouting from the roots. The most effective method of control is by herbicide application close to the flowering stage in late summer or autumn. In some cases it is possible to eradicate Japanese knotweed in one growing season using only herbicides. Trials in the Queen Charlotte Islands (Haida Gwaii) of British Columbia using sea water sprayed on the foliage have demonstrated promising results, which may prove to be a viable option for eradication where concerns over herbicide application are too great. (Source: Wikipedia)