1965] 
Nutting — Zootermopsis 
119 
relative humidity taken that evening at Pena Blanca — 92 0 and 33% 
at 6:30 P.M., and 78°F and 44% at midnight, following a typical 
warm day with showers in the vicinity during late afternoon. This 
pattern of flight behavior is considerably more restricted than the 
evening flights of Z. angusticollis which have been reported during 
every month of the year (Castle, 1934). The more even temperatures 
in the coastal regions may be more conducive to a longer flight period 
than the seasonal extremes common to the desert Southwest. 
Nesting site. Colonies have previously been reported in Fremont 
cottonwood (Populus Fremontii Wats.) (Townsend, 1893 ; Emerson, 
i960, in litt.) , alder (probably Alnus oblongifolia Torr.) and willow 
(Salix sp.) (Banks and Snyder, 1920) . Cazier ( 1962) has mentioned 
exposing portions of colonies in burls on living sycamores ( Platanus 
Wrightii Wats.) in Cave Creek Canyon between Portal and the 
Southwestern Research Station. Three colonies described in this 
report were found in willow (probably Salix Gooddingii Ball). 
Velvet ash (Fraxinus velutina Torr.), Arizona walnut [. Juglans 
major (Torr.) Heller] and perhaps netleaf hackberry (Celtis 
reticulata Torr.) would also appear to provide suitable nesting sites 
for this termite. In each case colonies have been found in unhealthy 
trees or in those which have contained at least some dead portions. 
The impregnability of the nesting site is dramatically illustrated 
by the first colony which was taken in a large Fremont cottonwood, 
on the flood plain 100 yards from Sonoita Creek and about two miles 
southwest of Patagonia. Fortunately the tree had been blown down, 
probably within six months or so, since it still bore many dried leaves. 
It measured at least 90 feet high and 6 feet in diameter at chest 
height. A few large nymphs of Z. laticeps were first discovered in a 
burl formed around the base of a broken branch on one of the main 
limbs. This limb, at the trunk, was 18 inches in diameter 40 feet 
above the ground and had been broken off at 23.5 feet, apparently 
some years before. The wet, fibrous bark was easily stripped off and 
the limb was then sawed into two-foot lengths starting from the 
broken tip. It was later sawed into shorter lengths, tracings were 
made of the cross-sectional cuts (Fig. 2), and finally each section was 
carefully split and the entire colony removed. The colony was thus 
Figure 2. Longitudinal section shows a reconstruction of the galleries of 
Zootermopsis laticeps in a cottonwood limb from Patagonia, Ariz. The 
actual numbers of nymphs (N) and soldiers (S) are indicated in each 
segment. Cross sections represent tracings of the galleries in the seven 
cuts AA to GG. 
