Your trees need Mychorhizal fungi.

What is it?

Mychorrhiza is a big greek word that means root fungus. It is a fungus that associates with the roots sending out fine filaments that can extract water and nutrients from the soil. These filaments are smaller that the smallest roots and can retreive nutrients that roots cannot reach. In exchange the tree gives back sugars and starches to fee the fungi.

95% of the plants on earth have Mychorrizae associated with their roots. Studies of plants with and without the fungus show a dramatic improvment in growth and survival.

When we build homes or compact the soil the Mychorhizae is destroyed so replacing it as part of a fetilization program yields healthier more vigorous trees.

Yes. Mychorrhizae do at times produce mushrooms above ground, but those shown here are just for illustration - the real action is in the ground.