82 CALIFORNIA CITRUS CULTURE. 
price. Until within the last few years the owner of a small orchard 
was not thus benefited unless the association to which he belonged or 
the county bought his materials. A co-operative company in the south- 
ern part of the State composed of the citrus growers themselves and 
known as the Fruit Growers’ Supply Company, now gives its members 
the advantage of the prices obtained by making large purchases. 
BLOCK FUMIGATION. 
The spread of scale insects in citrus orchards is very rapid, and under 
ordinary methods of fumigation, where only part of a district is treated 
each year, there is always a source of re-infestation from the trees which 
have not been fumigated for from one to several years. To eliminate 
this condition it is exceedingly desirable to fumigate large blocks or 
tracts of orchards the same year and thus place each upon the same 
basis. This is known as block fumigation and should be encouraged in 
every possible way, as it has great advantages over the usual haphazard 
fumigation of a district. All citrus growers should possess ‘‘ Insects 
of California,’’ Monthly Bulletin, State Commission Horticulture, 
Vol. II, 1913, No. 1-2, which is mailed free on application. 
DECADENCE OF CITRUS GROVES. 
There has been no little discussion of late regarding deterioration 
of our citrus trees. The condition of some of our groves and the fact 
that increase of production does not keep pace with the increase in 
planting lends some apparent color to this contention. Yet we know 
that in Europe trees a century old are still vigorous and productive. 
Some of our oldest orchards in California have lost none of their health 
or productiveness. It has been suggested that our Washington Navels, 
in their developed excellence, have yielded some of their strength and 
vitality, and so may deteriorate while yet young; yet there are old 
Washington Navel trees that still show a maximum of vigor and pro- 
ductivity. 
The Real Facts. 
We must remember that our citrus trees are marvelous producers; 
they know no rest season—no off years. Does it not stand to reason 
then that they must have the very best care and attention? If they 
are suffering from insufficient food or water; if the soil is hard and 
compact so that aeration is impossible; if they rest on impervious hard- 
pan, then what wonder if they show decline or utterly suceumb, In 
