Jackpine in paper pot planted July 1972, extracted & photo June 1973. Deersdale, J.D.Irving.

Pot trial of Banksia grandis in soil infected with Phytophthora cinn; N.B. dead seedlings.

Potassium deficiency. Red pine, 2+1, nutrient deficiency.

Potassium deficiency in Corsican pine. Saint-Front, Dordogne.

Potassium deficiency in Corsican pine. Saint-Front, Dordogne.

Potassium deficiency in Corsican pine. Saint-Front, Dordogne.

Potassium deficiency in Corsican pine. Saint-Front, Dordogne.

Potassium deficiency, healthy and two degrees of chlorosis. White spruce, 3+0, nutrient deficiency, potassium.

Potassium deficient red pine. Ed White's experiment. N.B. sweep of stems which Ed says is symptomatic of the potassium deficiency. Pack Forest. Warrensburg NY.

Potassium fertilized Douglas fir, sampling cones. Person is Bruce Devitt. Photo Mike Meagher. Mt. Prevost near Duncan.