Key to Nutrient Deficiencies of Deciduous Fruit and Nuts

Symptoms generally appear first on older leaves.

(When youngest leaves are affected oldest leaves usually are falling.)

Element Deficient

1. Marked “islands” of chlorosis or necrosis between main lateral leaf veins suggest a herring bone pattern. Leaf margins not affected in early stages. Sometimes V-shaped green areas appear with apexes toward leaf tips. Leaf size may not be affected.

Magnesium

2. Leaf margins first affected, showing discoloration near upper or lower lateral edges; leaves laterally curling upward, smaller than normal. Marginal necrosis may be preceded by slight chlorosis. Marginal scorch.

Potassium

Symptoms generally appear on youngest leaves.

1. Young leaves chlorotic; veins remain green.

Element Deficient

a. Internodes markedly shortened near tip of shoot producing rosettes of small chlorotic leaves. Older leaves may appear bronze and fall easily.

Zinc

b. Internodes not markedly shortened near tip. Fine lace-like network of leaf veins green. Youngest expanding leaf may be devoid of green color. Leaves acquire some green color with increasing age.

Iron

c. Tip leaves chlorotic, main veins green, shoot tips frequently die back and new shoots grow out from lower buds producing dieback and witches‘-broom.’

Copper

2. Young leaves not chlorotic or only slightly so.

a. Young leaves may be curved boat-like; shoot tips may be curved; terminal buds aborted and new shoots die back.

Boron

b. Midribs of leaflets shortened, tips rounded, wrinkled, and cupped.

Molybdenum

Symptoms generally appear on any part or all of plant.

1. Leaves small, uniformly less green; reduced growth.

Element Deficient

a. Leaf petioles, lower side of main veins and young shoots show purple pigmentation during early stages of growth. This pigmentation may disappear later in season and leaf color improve.

Phosphorus

b. No marked pigmentation. Pale color may become worse with increasing leaf age.

Nitrogen

2. No marked reduction in leaf size. Pale green color between main veins with large lateral veins showing broad band of green. Very fine veins not distinguished. Increasing in severity late in season. Young expanding leaves usually do not show symptoms. Chlorotic pattern somewhat between that of magnesium and that of iron.

Manganese

Symptoms principally on fruit.

Element Deficient

1. Young fruit show corky lesions. Frequently internal necrotic spots in fruit or internal cork. Deep cracking of fruit may develop as they mature.

Boron