Yes, CoreTect Tree & Shrub Tablets Insecticide can be used to treat shrubs for aphids and scale. You would want to follow the usage rates that are on the product label for your specific application.
CoreTect Tree & Shrub Tablets Insecticide is labeled for Japanese Beetle adults on established trees, you would use 2-3 tablets per inch of trunk diameter or per foot of shrub height. It is not labeled for June bugs though and we are unable to find a systemic that could be used for the adults. Adonis 2F could be used for Japanese beetles adults and larvae (in turf), as well as Green June Beetles and larvae in the soil.
No, CoreTect Tree & Shrub Tablets are not labeled for flea beetles.
We would recommend using the Fruit Tree and Vegetable Systemic Soil Drench. It is labeled for flea beetles, as well as various other pests.
The CoreTect Tree & Shrub Tablets is not labeled for tiger moth caterpillars as these are leaf feeding insects. We recommend that you apply Hi-Yield Thuricide Concentrate; it is labeled for this insect. You will mix 2 oz. per 3 gallons of water (4 tsp. per gallon).