We were told you could put some sort of tar at base of apple trees to keep bugs from climbing. Do you know of such a thing and will it harm pets? Thank you.
Yes, there is fruit tree greese or glue bands available to attach to fruit tree trunks.
This can help in combination with horticultural soaps to deter insests.
Search for 'glue bands' or 'fruit tree grease'.
Your local greenhouse or garden center may carry this product for you.