Things You'll Need
1/2-inch drill bit
High nitrogen fertilizer
Trees are tenacious plants, and often their removal requires more than just a chainsaw. Some trees send out suckers from their root systems. which will occur even if the entire tree has been taken down and there is no energy producing foliage. Others will have enough stored energy in the roots to force the stump to produce sprouts. Left to their own devices, these sprouts will form leaves, begin to photosynthesize and in no time you are faced with a tree in that location again. Removing sprouts and suckers is time consuming but a necessary chore if you don't want that species in your garden.
Force the stump to decay at an accelerated rate. Drill holes in the top that are 2 inches apart. A small stump may need only six to eight holes while a huge stump will need up to 20. Fill the holes with high nitrogen fertilizer. Cover the stump with soil and let it rot. This will prevent future sprouts.
Apply a formulated glyphosate spray to the suckers or sprouts. It is a systemic that will go into the vascular system and kill the sprouts and the root system. Moisten the growth lightly but not enough to drip. One or two sprays should be enough to coat the growth.
Dip a paintbrush into triplocyr and paint the top of the stump when it is freshly cut. If it has been sitting for a while, take 2 inches off of it with a chainsaw and paint the chemical on the wood. The fresh cut means the cells are open and receptive to the chemical, which will soak in and kill the sprouts.
Control sprouts on trees you wish to keep by brushing on naphthaleacetic acid, which is a form of the plant hormone auxin and will prevent the formation of the sprouts. It will not damage the rest of the tree.
Prune off the sprouts or rub them off if they are small. They will die, but more probably will come back unless chemical methods are employed. Every plant is different, however, and some send tree shoots only when they are young.