Question 1

Does it work for grubs?

Accepted Answer

Short answer: No, it is not effective for grubs.  I used to use Spectracide's Immunox for treatment and prevention of lawn fungus, until they put a broad spectrum insecticide in there.  The Immunox currently sold will not only treat Fungus and insect pests, but will kill beneficial and vital insects like bees, ladybugs, butterflies, preying mantids, etc.  So there is no longer any good reason to use Immunox.  
For Fungus, consider one of the generic offerings of Propaconizole offered here at Amazon and elsewhere.  Very effective and gentle on the lawn.  
For grubs, consider Bayer "24 Hour Grub Killer Plus" with Dylox.  Apply it when grubs are active, and water it in heavily right away.  It is extremely and quickly effective, and then degrades in 48 hours to a week so that you do not have long lasting effects on beneficial insects.  Only if you can keep it out of your gardens and flowering trees, you can use Merit or Adonis for season long control of grubs in your lawn.

Question 2

will this be safe for Zoysia grass?

Accepted Answer

Zoysia is a turf grass as is St Augustinegrass so it should work.  Do a little more research.

Question 3

Can it be sprayed in a tow behind sprayer? If so mixing rate please

Accepted Answer

Use as directed

Question 4

can I use this spray for the fruit trees

Accepted Answer

I would not its for lawns and might not be good for fruit trees or vegetables. for fungus 
try, Daconil Fungicide Concentrate 16 oz. . Insects try, Ortho Flower, Fruit and Vegetable Insect Killer Concentrate, 32-Ounce
or insecticidal soaps . if you will eat anything you spray.

ASIN	B00FGPN6FU
Active Ingredients	Propiconazole,Lambda-cyhalothrin
Brand Name	Spectracide
Customer Reviews	4.4 4.4 out of 5 stars (2,471)
Global Trade Identification Number	00071121961877
Item Form	Spray
Item Weight	1.1 kg
Liquid Volume	32 Fluid Ounces
Model Number	96187
Part Number	HG-96187
Target Species	Insects
UPC	071121961877
Unit Count	32.0 Milliliters

Spectracide 96187 HG-96187 Insect Killer

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