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Specticle 20 WSP Pre-Emergent Herbicide is generally compatible with many herbicides and liquid fertilizers. A compatibility test should be conducted with any potential tank mix partner with Specticle 20 WSP Pre-Emergent Herbicide*. Using a clear container, conduct the test as described below:
1.Fill the container three-quarters full with water.
2.Add the appropriate amount of Specticle 20 WSP Pre-Emergent Herbicide** and the tank mix partner in the following order:
(a) Specticle 20 WSP Pre-Emergent Herbicide
(b) dry flowable
(c) aqueous suspensions
(d) flowables
(e) liquids
(f) solutions and emulsifiable liquid concentrates
(g) micronutrients and liquid fertilizers
3. Shake or stir after each addition to mix thoroughly.
4. After adding all ingredients, let the mixture stand for 15 minutes and look for separation, large flakes, precipitates, gels, and heavy oily film or other signs of incompatibility
5. If the compatibility test shows signs of incompatibility, do not tank mix the product tested with Specticle 20 WSP Pre-Emergent Herbicide.
6. If mixing with a liquid fertilizer or micronutrient, add Specticle 20 WSP Pre-Emergent Herbicide to the tank first and make sure it is fully dissolved before adding the fertilizer.
* Do not use Specticle 20 WSP Pre-Emergent Herbicide packets in a tank mix combination with products that contain boron or release free chlorine. The resultant reaction of PVA and boron or free chlorine is a plastic which is not soluble in water or solvents such as diesel oils, kerosene, gasoline, or alcohol.
** Note that a labeled spray rate for Specticle 20 WSP Pre-Emergent Herbicide should be used in any compatibility test. Dilute from a concentrated suspension, or sample from a properly dilutedspray solution. Do not cut the water soluble packs open for any reason.
Specticle 20 WSP Pre-Emergent Herbicide will prevent annual sedge only, but not yellow or purple nutsedge. Yellow and purple nutsedge are best controlled with post-emergent emergent herbicides since there is very limited pre-emergent control for them. Specticle would be safe to use around listed established warm-season turf and established ornamental plants. Specticle should not be used around olives or other plants that produce edibles. The product label does list red knockout roses and a few others as tolerant, but it does not specifically list iceberg roses. We would suggest testing a small number of plants before applying over a large area. Our most popular post-emergent herbicide for yellow nutsedge is Sedgehammer Herbicide.
Specticle 20 WSP Pre-Emergent Herbicide cannot be applied through an irrigation system.