River Birch Nutritional Problems

nickel def1

Nickel deficiency symptoms in river birch are called mouse ear because the leaves become very small and have a curled upper edge.

During the summer of 2012, which was hot and dry, I observed river birch trees (Betula nigra) in northeast Florida with symptoms I had not seen previously. The leaves of new growth were smaller about 1/4 their normal size with a distorted, somewhat rolled distal end. Severely affected branches can defoliate and eventually die.

At first I suspected herbicide damage. But after seeing the problem on nearby properties that did not have the same landscape maintenance company, I ruled out herbicide as the cause.

I then remembered an obscure nickel deficiency. It has a name — mouse ear. Nickel deficiency is normally found on river birch nursery stock grown and less frequently in the field. Nickel deficiency is more commonly found on pecan trees but I have not seen it on pecan trees in northeast Florida.

nickel def2

Once treated for nickel, the new flush of growth had normal sized leaves within four weeks following treatment. The chlorosis cleared up shortly after the photo was taken.

I found the product and appliced it as a foliar spray and a soil drench. Within four weeks new growth had begun to emerge without the mouse ear symptoms.