For home owners, one of the handiest tools for feeding trees is the injector probe or "needle." This is a hollow steel rod three or four feet long, sharp and perforated at the business end. It has a glass or plastic chamber at the top, under the handle, to contain a cartridge of food concentrate. It attaches to your garden hose. It costs up to eight dollars, the cartridges about twenty-five cents each. One cartridge will dissolve in and sufficiently enrich about 100 gallons of water, enough to invigorate a twenty-inch diameter tree. (The approximate diameter is one-third of the length of a string that will encircle the trunk, breast high.) With forty pounds of pressure on your water line, in moderately loose soil, one hundred injections of about a gallon each can be put down in less than an hour. Your hired man can easily "needle" a dozen average trees in a day, or you can do as much yourself over a lazy weekend without blisters or a sore back.

Liquid feeding by injection is a short-range method. Its effects are quick but transient. It is valuable for trees needing a prompt shot in the arm, since the nutrients are immediately available, in aqueous solution. But much virtue may leach away before the tree has imbibed all its needs.

After anemic trees are thus invigorated, the experts recommend a lasting supply of solid food, such as suffices for non-critical cases. The home tool for this is a punch-bar, pointed at one end, wedge-shaped at the other. Any schoolboy of moderate strength can learn to drive the wedge into turf at an angle, to raise and lay back a broad divot. From the opening thus made, a pound or so of soil is scooped out and piled nearby for replacement later. The bar's sharp end is now plunged into the hole repeatedly, deeper and deeper. Work the buried point back and forth on each stroke to loosen the subsoil and at the same time ream out the hole's mouth. Rocks and hardpan permitting, the holes are driven 18 to 24 inches deep.