49 CHAPARRAL. 
crassifolia, and grease-wood, for example, than where the stand is a 
mixture of oak, sumac, and buckthorn. 
Burned chaparral areas will eventually restock with chaparral 
species. The rapidity with which the new cover is established de- 
pends upon the severity of the fire, upon the proportion of species 
in the original stand which will coppice from the roots, and upon 
the position and species of chaparral around the burned area. These 
variable and uncertain factors make it difficult to say with certainty 
how long it will take to recover a burned area. If a stand of the 
taller chaparral, such as ceanothi, was totally destroyed, it might 
be 20 or 30 years before the cover is fully restored. On the other 
hand, a mixed stand of rhus and quercus, if burned, would quickly 
restock the ground with a dense cover. In general, however, 10 
years are required to restock a burned area to the extent that its 
hmits are not clearly defined to the casual observer. 
The new crowns which spring from old roots after a fire in the 
chaparral are of the greatest importance in the establishment of a 
new cover, because they insure the presence in it of fire-surviving 
plants. 
ARTIFICIAL RESEEDING. 
There are many places in the chaparral area barren of growth 
now, and which, because of some accident of situation or climate, are 
not likely to be forested by natural means; and there are others 
where the chaparral cover, if it comes at all, will be composed largely 
of undesirable species. In such situations the only course open to 
secure the necessary cover is artificial sowing. The most extensive 
experiment in the artificial seeding of chaparral was made by Mr. 
T. P. Lukens in the San Gabriel Forest Reserve, now a part of the 
Angeles National Forest, in 1902. Rhus lauwrina was the species 
used, since it will grow on very steep and rocky slopes, furnishes 
good shade, is not easily killed by fire, and sprouts from the old roots. 
In all, about a thousand pounds of seed were scattered. One plant- 
ing site was on a rocky cliff, several hundred feet high, facing the 
east, below the astronomical observatory on Mount Wilson. Astrono- 
mers had been annoyed by heat waves rising from this cliff, which 
made it difficult on sunny mornings to use the optical instruments. 
No attempt was made to remove the glutinous covering from the seed 
before sowing. The greater number of seed were sown from the 
brink of the cliff, with the idea that the natural fall would distribute 
them fairly evenly over its surface. “On the whole the experiment 
was successful; many trees have started upon the cliff, which prob- 
ably will, in time, be thoroughly covered—this despite the fact that 
the elevation of the site, 5,000 feet, is high for the species used. 
Another sowing of the same species was made on the hot slopes 
below Henningers Flats, but this was followed by a drought of 
