FERTILIZER BASKETS - Used to enclose solid fertilizer in order to prevent disturbance by birds.

Each tiME the tree is watered a portion of the fertlizer is washed through the soil.

There a number of designs : some (as illlustrated) are placed over the top of the solid fertilizer and some have lids on top and spikes on the bottom so that the fertilizer is self-contained while the spike keeps the basket firmly positioned in the soil.