Smart phones have them internal gyroscopes. Download an app which lets you take a picture and displays the angle your phone was at. Pretend the tree is the straight part of a right angle triangle. I prefer to get as far away from your tree on level ground as necessary to see the top leaves when lying on the ground. For some odd reason I prefer if the angle is exactly 45 degrees but if you measure the distance from the tree to where you took the pic you should be able to calculate the other legs of the triangle.

Thanks for the photo comments. The picture is from 2006 and is the rhubarb remaining immediately after a harvest, where all the older stalks on the ground and at low angles have been pulled off. Slug bait pellets are used around this rhubarb on occasion. It is about time for harvest #2 this year. Local strawberries should be widely available by mid-month. Some U-pick notices are already in the paper. The Barn rhubarb is still on display during peach season when we visit.

I think I've been mixing up the parts! I know I had searched previously, but found a really good article today that really explains it well!!

Please do not use dish soap as an insecticide for any plant. Detergents Dishsoap/ detergent’s effect on plants varies with the mode of exposure. Dawn, Palmolive, Joy, ...... dishsoap, as examples, are each and all a mishmash of chemicals, at least eleven of which are phytotoxic. If the top of the plant is sprayed thoroughly with even mild detergent solutions such that all surfaces including leaves are covered, the detergent can easily dissolve the protective coating of cuticular wax on the leaves of the plant, causing abnormally high rates of water loss and possible necrosis of all or part of the leaf. Cuticular waxes prevent leaves from drying out, and help stop pathogens from attacking the leaf. Strong solutions will even dissolve cell membranes, causing death of the cells. If a detergent solution is used as a soil drench or makes its way into the soil as a consequence of over-spray or run-off, the effect on roots is immediate. Because one of the main function of roots is to absorb water and nutrients dissolved in water, they lack the waxy protective coating that leaves employ. Detergent solution in contact with root cells can quickly dissolve the lipid membrane surrounding cells, killing the cells and inhibiting water/ nutrient uptake. Hair cells growing as appendages off larger roots do the lion’s share of assimilating water and nutrients, and these very delicate cells would be the first casualty of any detergent in the root zone. There are widely available insecticidal soaps, designed to be used topically and made mixing potassium with only long chain fatty acids, carefully selected and specifically formulated to be safe for mammals & birds, death on most insects they contact, and most important, safe for plants. If you need something "soapy", it would be much better if you selected a product intended for use on plants than one intended for other purposes. Al