1930] Praca CuLTurkE IN CALIFORNIA 17 
Elberta, Muir, and occasionally clingstone varieties. Pits are obtained 
oither from canneries or dry-yards. The peach rootstock succeeds best 
on deep, light, well-drained soils, but it does not withstand heavy wet 
soils. The peach root is also susceptible to injury from alkali. In the 
foothill sections peaches are sometimes grown on soils not over three 
feet deep. Such trees, however, do not grow so large and do not 
appear to be so long lived and productive as those grown on deeper 
soils. The peach root is subject to attacks of the peach root-borer, 
crown gall, soil nematode, and oak root fungus. When free from 
pests and under favorable soil conditions the peach root is long lived. 
Under California conditions, while the peach top deteriorates after 
25 to 30 years, the roots may live longer. 
The Apricot Root.—The apricot root will grow on a wide range of 
soils, but does best on a moderately heavy, well-drained, fertile soil. 
The root is more subject to attacks by gophers than either the peach or 
almond. Crown gall, oak root fungus and the peach root-borer, also 
attack this root. The possible value of the apricot as a rootstock lies 
in the faet that it is resistant to the attacks of the soil nematode, which 
is a serious pest in certain soils of the San Joaquin Valley and of 
southern California. Attempts have been made, therefore, to propa- 
gate peaches on apricot root. The results, however, have not been 
entirely satisfactory. The union is sometimes uncongenial although 
there is no tendency to break. When the peach is budded six to eight 
inches high on the seedling or topworked upon the apricot it is claimed 
that it does better than when budded near the ground. It is reported 
that there are a few peach orchards in Riverside county, in Kern 
rounty, and elsewhere that are upon apricot roots. The use of the 
apricot as a rootstock for the peach is still in an experimental stage. 
There is a possibility that a variety of peach may be found whose 
seedlings may be resistant to nematode attack. 
Prunus Davidiana as a Rootstock.—Seedlings of Prunus davidiana 
are considered promising as a rootstock for peaches for planting in 
spots of the orchard where the original trees on other stock have died 
because of alkali. This root is resistant to injury from alkali, and has 
heen used as indicated above, in parts of Tulare and Sutter counties. 
The peach on this rootstock appears vigorous, with green foliage, 
ander conditions where the trees on other rootstock have yellow foliage, 
stunted growth, and are gradually dying. According to F. W. 
Anderson of the Kirkman Nursery Co., however, this rootstock is not 
being used by nurserymen because it is extremely susceptible to crown 
gall.