The Problem
Goosegrass (Eleusine indica) is a tough, dark-green, clumped summer annual, generally with a “whitish to silverish” coloration at the center of the plant, which is the source of another of its common names, “silver crabgrass”. It thrives in wet, compacted soils such as those adjacent to cart paths, or walkup areas to tees and greens. Goosegrass can withstand golf green mowing heights. It reproduces by seeds which germinate in spring when soil temperatures at 4-inch depth reach 63-65°F for 24 continuous hours. This often corresponds to the flowering of dogwoods and azaleas. Alternating warm and cool temperatures also highly favor germination, which is typically 2-4 weeks later in spring than crabgrass germination. Germination occurs when seeds are on the soil surface, but no germination occurs at 3-inch depths. Thousands of seeds are produced annually per plant, and these can remain viable for 6 or more years, are produced annually per plant. Goosegrass perennates in subtropical regions lacking sufficient yearly frosts to kill it. Herbicide resistance has been reported with the dinitroaniline herbicides, glyphosate, oxadiazon, fluazifop-ethyl and diquat, but only in isolated instances. Rotating between herbicides with different modes-of-action is the best means of preventing, or at least delaying, resistance occurrence.
What To Look For
Goosegrass is most frequently found in high-traffic areas where the turfgrass cover is thin. Stems are often compressed (flattened), originating from a central point, forming a mat-like rosette, but not rooting down at the nodes like crabgrass. Leaf blades are smooth on both surfaces, occasionally with a few hairs near the base, and have folded vernation. Leaf sheaths have white margins. A short-toothed, membranous ligule is visible at the base of the leaf blade, divided at the center. Auricles are absent. Often leaf blades are frayed by dull mowers and tips develop a whitish cast. Seedhead spikelets are in two rows on 2-13 branches, resembling a “zipper”, which form from mid-summer until frost. Flower branches are windmill-like in that they emerge from a common point.
The Solution
Preemergence Solutions
In warm-season turf, goosegrass control begins with an application of a preemergence herbicide. Key Envu solutions for preemergence control include Ronstar® and Specticle®. Both products should be applied prior to typically anticipated germination in late winter/early spring. Ronstar is the industry standard on warm- or cool-season turf. Ronstar can be sprayed or spread on dormant warm-season turf even before winterkill status has been confirmed since it can be sprigged into successfully. Ronstar on fertilizer can be used on cool-season turf and on non-dormant warm-season turf. Goosegrass control also has been excellent with Specticle, but should be used only on well-established turf that isn’t affected by nematode damage, spring dead spot, insufficient establishment, winter kill, shade, etc. If these conditions exist, wait to apply Specticle until turf has recovered or consider Ronstar instead.
Postemergence Solutions
For postemergence control of goosegrass, Revolver® and Tribute® Total can be used in bermudagrass and zoysiagrass. Other postemergence herbicides in bermudagrass and zoysiagrass golf turf include Sencor® tank-mixed with MSMA. Selective goosegrass control in seashore paspalum is currently unavailable, though spot applying rock salt is often used to control it. On cool-season turf, Acclaim Extra is the preferred Envu option. On sites with traditionally heavy goosegrass populations, both programs including both pre- and postemergence products are typically required for sufficient control.
Additional resources
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Solution sheet - Goosegrass |
