EUCALYPTUS 
305 
the floor board. The temperature at this 
point should be approximately between 48 
and 52 degrees to insure 57 or more within 
the cluster. If it is below these points the 
entrance should be contracted. Jf the tem¬ 
perature on the floor board reaches 60 to 
65 degrees the entrance should be enlarged. 
From these considerations it will be seen 
that no definite size of entrance can be 
prescribed for all the colonies in the cellar, 
unless the colonies are of about equal 
strength. 
Colonies could be divided, perhaps, into 
two or three different groups as to strength. 
The temperature reading on the floor board 
the qualities of which are being tested and 
compared. To a much smaller extent they 
have been planted in Arizona and the Gulf 
region of Texas. Few eucalyptus trees will 
endure a temperature below 20 degrees, or 
above 120 degrees F. They grow very rap¬ 
idly and promise to become very valuable 
sources of timber and other commercial 
products, and are likewise very effective 
as avenue and landscape trees. A number 
of the species are popularly known as gum 
trees because a resinous gum flows from 
incisions in the bark; others are called 
iron-bark trees from their very hard bark, 
and still others from their fibrous bark are 
The eucalyptus is of vast importance in California for brood-rearing. 
should be taken of about a dozen of each 
group. The entrances of these colonies 
should then be regulated to a point between 
48 and 52 degrees. All other colonies of 
the same group should have entrances of 
the same opening. 
EUCALYPTUS. —A large genus of ever¬ 
green trees growing chiefly in the coast 
region of Australia and New Guinea. 
About 150 species have been described, of 
which not far from 100 have been intro¬ 
duced into California. At the Forestry 
Station at Santa Monica there have been 
planted nearly 70 species and varieties, 
termed stringy-bark trees. To this genus 
belongs the tallest tree in the world, E. 
amygdalina, which attains the height of 
480 feet. 
By far the most widely planted and 
probably the best adapted to the climatic 
conditions of California is the blue gum, 
or E. globulus, which is found in almost 
every town in the State from San Fran¬ 
cisco to San Diego, and inland as far as 
the edge of the Imperial Desert region. It 
is apparently as vigorous in California as 
in its native Australia. It is claimed to be 
the fastest growing tree in the world. 
Seedlings will average a growth of 50 feet 
