Increase water volume to kill scale

We have had a hard time killing the white peach tree scale on ash, but no one has mentioned difficultly in killing it on lilac or mulberry.

I suspect we are not getting sufficient coverage with our air blast sprayers on our trees. If anyone has learned a secret, I hope they will share it. If you are having difficultly killing it, let me know. We need a test site.

Dr. Hale mentioned early that summer applications had to be timed with the emergence of the crawler stage and we shared ways to detect that, such as double sided tape, etc.

I have continued to chase: systemics, increasing water volume per acre, etc. Some of the systemics are $260 to $400 per treated acre, applied in a band over part of the root zone or by watering each infested tree with 1 quart of the solution per inch of stem caliper. A 2 inch tree would need 2 quarts.

It seems that most of the air blast sprayers I have checked were applying around 35 gallons of water per acre. Most operators already drive rather slow. Two producers shared they have backed the rpm?s down and think they are getting better coverage. Tom Young with Leinbach?s agreed.

I did learn today from General Equipment about 2 black levers on the Jaccto sprayers. One black lever turns it on and off. Another has settings of 1 to 5.5. The higher number increases the water volume. Are you using the higher setting to spray scale?

Regardless of the brand, most sprayers should have a way of increasing the water volume per acre. Check the book or check with your dealer. Changing the tip size will probably be the easiest and most effective way. Gen. Equip. can order larger spray tips for the Jaccto and have them here in a matter of days.

I have spoken with our fruit tree specialist. Fruit orchards are also having more problems with scale, in recent years. They routinely spray oil at 100, 200 and even 250 gallons of solution per acre. They wash the trees with oil; trying to put it in every crevice. They drive every middle N-S and E-W. We can only spray from 2 sides.

They also add an insect growth regulator to the oil and are obtaining excellent control. Dr. Hale and I may try some, but we need scale.

Would you prefer to wash your scale infested trees from top to bottom and sideways with 100 gallons or more of solution per acre, using an air blast; band spray the soil with 100 gallons of water per treated acre like we do with Discus, driving every middle; or pour (drench) 1 quart of solution per inch of caliper around each infested tree?