8 BULLETIN 743, U. S, DEPARTMENT OF AGRICULTURE. 
The fig is also grown in this zone; and the indigenous cherry {Primus 
solid folia H. B. K.), which is very common in gardens, descends into the 
subtropical zone, but is most frequent at elevations of 7,000 to 9,000 feet. 
The upper limit of this zone is the upper limit of cultivation. One of the 
highest towns in Guatemala is San Francisco el Alto, north of Quezaltenango, 
at an elevation of 9,000 feet, but above this there are occasional huts, around 
which a few fruit trees may be found, while the grain fields extend to 10,000 
feet or higher. 
Summing up the characteristics of the three zones, it may be said 
that the lower or tropical zone is a region of comparatively high 
temperatures throughout the year, never experiencing cold weather, 
and hence adapted to the cultivation of those fruits which horticul- 
turists term strictly tropical in their requirements. The subtropical 
zone, owing to its greater altitude, is free from the extreme heat of 
the tropical zone, but is never subjected to severe freezing. The lower 
levels of this zone are fairly warm throughout the year, but toward 
the upper limit the winters are decidedly cool, strongly resembling 
those of southern California. The uppermost zone, here called the 
semitropical, is too cold for the orange and the lemon, yet does not 
experience the type of winter weather familiar to residents of the 
eastern United States. Its minimum temperatures probably more 
closely approach those of southern Texas and central Florida. The 
principal fruits grown in this zone are the apple, peach, and pear. 
In regard to rainfall, the quantity varies greatly in different parts 
of Guatemala, but the season during which it occurs is more or less 
the same throughout a large part of the country. Figures for several 
regions are given in considering the Guatemalan race of avocados. 
In general, it may be said that the rainy season begins in May and 
continues until October, being at its maximum during August and 
September. In the Yera Paz district of northern Guatemala, how- 
ever, it rains during most of the year, the only dry months being 
March and April. On the coast the precipitation is usually much 
heavier than in the highlands, and in certain regions^ such as the 
valley of the Motagua River between El Eancho and Gualan, there is 
comparatively little rainfall at any time of the year. In the high- 
lands the dry season is often severe, practically no rain falling from 
November until April or May. The roads become deep in dust, 
the herbage turns brown, and many of the woody perennials drop 
their foliage. 
CLASSIFICATION OF AVOCADOS. 
The classification of avocado varieties has been the object of much 
investigation in California and Florida during the last few years. 
As with many other cultivated fruits, it has been found that the horti- 
cultural varieties fall into several distinct groups. Three of these, 
termed generally the Guatemalan, West Indian, and Mexican, are 
now recognized by most investigators. 
