William from Nellysford, Va writes
I have a large area of ivy ground cover that has been doing quite well until the Japanese Stiltgrass showed up and left an ugly straw-like mess after winter die off. Snapshot was recommended, which seemed to do the trick. But now the Ivy is struggling mightily. Did I put on too much Snapshot (killing the ivy slowly?) or too frequently (every 60 days). Is twice a year enough (early March and then June). Or is Snapshot not the correct stuff to keep Stiltgrass out of the ivy ground cover? What else would work better?
Unfortunately, since Snapshot 2.5 TG does not specificaly list Japanese Stiltgrass as one of the weeds controlled, there is no information to determine a recommended application rate. This product is labeled safe for many varieties of ivy including english, Algerian, and ivy geranium but would not be used on morning glory ivyleaf as this is listed as a weed controlled at the 150lb per acre rate. Under General Use/Application Instructions Section on page 2 of the Snapshot 2.5 TG product label, it advises that repeat applications at the 150lb per acre (3.45lbs per 1000 sq ft / 0.35lbs per 100 sq ft) or 200lbs per acre(4.6lbs per 1000 sq ft / 0.46lbs per 100 sq ft) should not be made sooner than 60 days following the initial application. If applications were not watered in sufficiently with atleast 0.5 inches of water or if the granules overlapped, this can cause injury to desirable ground covers. A better option for pre emergent control of Japanese Stiltgrass in landscape beds would be Dimension 2EW. This product is tolerant to English Ivy and does specifically list Japanese Stiltgrass (Mary’s Grass) is as a weed controlled. Application rate is 0.73 fl oz per gallon of water per 1000 sq ft or for smaller areas, 0.073 (2.2 ml) per 16 to 32 oz of water. Apply in a single application or sequential applications at 5 to 10 week intervals. View the full product label for more information. During growing season and summer months, japanese stiltgrass can be controlled with Acclaim Extra that is a post emergent herbicide labeled to control Japanese Stiltgrass and safe for English Ivy ornamentals/groundcover. Please review the full product label for more information Pre emergents work best for this weed when applied before stiltgrass germinates which occurs several weeks before crabgrass germiantion. Contact your County Extension Office for exact timing recommendations for your area.
Answer last updated on: 06/13/2022