Unfortunately, insecticides like Zylam or any other systemic products are generally of no use to treat ambrosia or other boring beetles in trees. These beetles will not ingest the active ingredient, and trees infested with these insects are often already weak from disease, drought, other conditions before the beetles infest them. You can try trimming and destroying infested branches and spraying nearby susceptible trees with a preventative insecticide such as Talstar P. Fully infested trees will usually need to be removed and destroyed. This article from the Clemson Extension Service goes into more detail about ambrosia beetles.
Yes, Zyalm Liquid Systemic Insecticide can be safely used for leaf notchers on orange trees, but only if they are non-bearing fruit trees. This product cannot be used on trees that fruit would be harvested from. Depending on how you use the product, either foliar application or soil drench would determine how many trees this bottle could treat. Please see the following for each application which is directly from the product label:
Foliar Application: 8 - 16 oz per 100 gallons. Apply in sufficient water to ensure thorough coverage of targer area. Use a minimum of 50 gallons finished spray per acre. Do not appy more than a total of 39 oz of product per acre per season as foliar spray. Start treatment prior to buildup of high pest populations. Foliar sprays: 100 gal of spray mix will treat 20,000 sq.ft of area.
Soil Drench: Small Trees (Less than 20 inches diameter at breast height) 0.2-0.8 oz per inch diameter at breast height. Large Trees (24 inches diameter or greater at breast height) 0.4-0.8 oz per inch diameter at breast height. For Multi-Stem trees, base rate on cumulative inches of diameter of all stems at breast height. For optimal control, apply early in the plant's annual growing cycle and keep soil moist for at least 7 days after application. Only apply to moist soil. Do not apply to dry, saturated, or frozen soil. Heavy rainfall or inadequate irrigation immediately following application may decrease performance.
According to the Product Label, Zylam has been tested to be used on the following types of scale: Scale (Armored and Soft) including Azalea Bark, Brown Soft, Calico, Cottony Cushion, Cycad Aulacaspis, Cyptomeria, Duplachionapis, Elongate Hemlock, Euonymus, False Oleander, Fig Wax, Fletcher, Florida Red, Florida Wax, Lecanium, Oystershell, Poplar (Aspen), Pine needle, Tea, Tulip Tree . While Crape Myrtle bark scale is not specifically listed it could be controled as well by the Zylam if applied properly. You may want to contact PBI Gordon at 8 0.821.7925 since they will be better experts on what their product may also be able to treat before applying this product.
First, you must identify what the source of the problem is in order to correct it. We recommend that you contact a certified arborist and have the tree inspected for stress, disease, or insect damage. What you are describing could be contributed to a whole host of causes. Once the cause has been idetified then please contact us back and we would be happy to make a proper product and treatment recommendation.
Per the manufacturer, they do NOT recommend applying Zylam Liquid Systemic Insecticide in greenhouses or on orchids. It is to be used outdoors only in landscaped ornamentals. Please refer to the label by clicking the link below for more detailed information.
http://www.domyownpestcontrol.com/msds/ZylamLiquid-SL.pdf
We do carry Safari which is labeled for greenhouse use and for soft, brown scale. I do not see orchids specifically listed on the label but you can contact the manufacturer for usage information at Valent USA Corp 800.682.5368
