FOREST TREES OF THE PACIFIC SLOPE. 335 



California Sycamore. 

 Platanus racemosa Nuttall. 



DISTINGUISHING CHARACTEKISTTC8. 



California sycamore, also called "buttonwood" and " buttonball," is small or 

 medium sized; from 40 to 60 feet high and from 18 to 30 inches in diameter. 

 Trunks are often very short, giving off several trunk-like branches. The 

 branches are conspicuously irregular in the directions they take. One or more 

 of them may reach out low to the ground, while others wind and twist in pros- 

 trate or upright positions. Thick. long, crooked, and awkwardly bent, they 

 form an exceedingly open crown. Such trees grow mainly in the open. Crowded 

 in the bottoms of deep canyons California sycamore occasionally reaches a 

 height of 75 or 80 feet (rarely more) and a diameter of from 3 to G feet. The 

 dull brownish bark is ridged and furrowed at the base of the trunk. At the 

 bases of old trunks it is from 2 to 3 inches thick : a short distance above, and on 

 all of the limbs, it is very thin, smooth, and ashy white, with greenish-gray 

 areas. Thin layers peel off annually, broken by diameter growth, keeping the 

 upper parts of the trees smooth and conspicuously white. 



The thick leaves (fig. 150), from 5 to 11 inches long and wide, are light yel- 

 low-green, much lighter beneath ; they are minutely and densely hairy, especially 

 on the midveins and their branches, though the amount of hair is variable. From 

 4 to 5 male flower heads are borne on a thread-like stem which grows from a leaf 

 cluster on branches of the previous year; and from 2 to 7 (commonly 4 to 6) 

 female flower heads grow on a similar stem which usually terminates a new 

 branch of the season. The latter develop into bristly fruit heads (fig. 156), 

 three-fourths inch to nearly an inch in diameter, with a single stem 5 to about 10 

 inches lung. The slender, bristly seeds (akenesi are from three-eighths to seven- 

 sixteenths of an inch long (fig. 156, a I. Wood (described under Platanus) is not 

 specifically distinct from that of the other sycamores. 



Longevity. — Age limits not fully determined. Believed to be long-lived. A 

 ■ingle tree 20} inches in diameter showed an age of 86 years. Exceedingly tena- 

 cious of life, repairing repeated damage to its crown and trunk by vigorous 

 sprouts and growth of wood. 



RANGE. 



California (from the lower Sacramento River through interior valleys and coast ranges) 

 to Lower California (San Pedro Martir Mountain). In the north tip to 2,000 feel and in 

 the south to 4,000 feet Plumas and Lassen Peak National Forests in foothill type up 

 to 2,500 feet. Farther south in Sierras noted at. White Deer Creek (northwest tributary 

 King's River), on King's River from Trimmer Springs up to near mouth Big ("reek and 

 thence south, in Bis Creek Canyon and on Northeast Branch Mill Creek, along lower 

 Kaweah and In Tehachapi Mountains. On Lytle Creek, Caliente Creek, lower end Canada 

 de las Fvis. lower part Tejon Canyon and along P isi Creek, bul not down desert streams 

 to the east. On coast ranges noted on Carmel River up from mouth and alons all stream 

 beds of Santa Lucia Mountains from sea level to 2,000 feel : San Luis Obispo National 

 Forest up to 2,500 feet on watersheds of Carriso. Salinas. Santa Margarita, San Luis. 

 Arroyo Grande. Huasna. and Santa Maria. Santa Barbara National Forest in watersheds 

 of Santa Ynez, Santa Barbara, Matilija, Piru-Sespe, Elizabeth, and Newhall rivers, at 

 loo to 4,200 feet San Gabriel National Foresl up to above 5,000 feet; noted near Pasa- 

 dena on Oak Knoll. Arroyo Seco, and canyons of San Gabriel Mountains. Santa Ana 

 range in canyons. San Bernardino Mountains, western and southern slopes, 1,600 up to 

 3,000 feet. Sas Jacinto Mountains, western slope, below 4,800 feet. On Palomar 

 (SnTithi. Balkan, and Cuyamaca Mountains, from western side nearly to summit, and 



weal nearly i :ean. 



0< ( t 1:1:1 \i k. 



Confined to or near borders of perpetual and Intermittent streams and moist gulches; 

 in poor, rocky soil. Forms sparse lines and small groups of pure growth, or is mixed 

 with white alder, broadleaf maple, California walnut, and occasional willows. 



