Bui. 1477, U. S. Dept. of Agriculture 
Plate 1 7 _^ 
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Growth, Fruit Spurs, and Fruiting Habits of the California 
Blue Plum in Relation to Pruning and to Soil and Other 
Conditions 
A.— Branch of a tree which has not been pruned for several years. Note that much of the 
new growth is from the tips of branches and that spurs are retained along older wood. 
The tree is growing in fertile irrigated soil. (Newcastle, Calif.) 
B. — Branch of a tree which has been severely headed back each year and is growing in 
fertile irrigated soil. Note the vigorous growth of shoots and twigs in all parts of the 
tree. (Compare with A. Newcastle, Calif., May 26, 1923) 
C— An 8-year-old branch of a vigorous tree. Note the new spurs (near pencil) which are 
growing at points where old spurs were broken off last year 
D. — A 7-year-old -branch of a tree which has been very lightly pruned. Note the persistent 
and fruitful spurs, instead of twigs and shoots such as appear on severely pruned trees. 
(Compare with B. Newcastle, Calif.) 
E.— A 1-year-old fruiting twig of a thrifty tree. Note the production of fruit at numerous 
nodes where spurs are forming on this 1-year-old branch. A strong varietal tendency 
to produce spurs is indicated. (Newcastle, Calif., April 11, 1923) 
