674 EXPERIMENT STATION RECORD. 



blackberry, and strawberry, lilac, mock orange syringa {Philadelphus 

 coronarius), liorse chestnnt, red pith elder {Sambucus racemosa), com- 

 mon elder {S. canadensis), lowering dogwood {Cornus Jlorida), na^tive 

 basswood, native chestnut, privet or prim {Lignstrum vulgare), red 

 currant, and cultivated grape. 



In addition to the events to be recorded as mentioned by Hotimann, 

 the author thinks that there should probably be included the date of 

 nearly complete defoliation ibr those species whose leaves color some 

 time before they fall. All unusual flowering seasons should be recorded, 

 but they should be distinctly marked so as not to be confounded with 

 the normal events, and all sudden meteorological changes, as frosts in 

 the fall and spring and high winds when defoliation takes place, should 

 be observed. 



In conclusion, it is stated that persons spending their summers at 

 resorts on the mountains or elsewhere can make useful records, provid- 

 ing they visit the same i)lace year after year. They can select a few 

 typical plants, and observe their conditions at the time of their arrival 

 and departure. At the same time they can make records of progress 

 of harvests, of hay and grain, and other staple crops. 



Climate of the Foothill Station, California, C. II. Shinn and G. 

 Hansen {California ISta. Rpt. ISfJo^pp. 358-364, figs. 2). — This station 

 is located in the Sierra foothills, 5 miles northeast of Jackson, at an 

 elevation of a little less than 2,000 ft. above sea level. General notes 

 on observations on climatic phenomena since the establishment of the 

 station are given, with a monthly summary of observations on tem- 

 perature during 1804, 189.'», and a part of 1892, on the top of the highest 

 hill on the station farm and at a point in a valley about 200 ft. below. 



"The Foothill Station does not possess a climate in any way remarkable as com- 

 pared with numerous localities at similar elevations in the Sierras. It has what is 

 better, a. typical foothill situation, surrounded by peaks, ridges, and depressions of 

 greater or less extent, giving it the general characteristics of a so-called 'thermal 

 belt,' or thermal si>ot, thousands of which exist nndescribed throughout California." 



It appears that these thermal belts do not occur at a greater eleva- 

 tion than 2,000 ft. above sea level. 



"The warm air travels from our valleys to the snow-capped Sierras, and the cold 

 air moves from them to the lands below. The path which they travel is varied by 

 every hill and curve in the canons. . . . 



"Along the canons flows the cold heavy air from the Sierras, frost-killing what- 

 ever is in its path, if too tender for the season. If such cold stream of heavy air is 

 too voluminous, jt has to overflow into a side canon. The space which these cold 

 rivers occupy was previously held h\ warm air, which was lighter, and had to give 

 way, rising above the level of the cold. Wherever it goes is the warm region, the 

 thermal belt. . . . 



"Thermal belts favor the farmer, because the season of growth is longer thau else- 

 where. While in early spring the sun warms the low places, and forces vegetation 

 into growth, though it is apt to be frosted, the air in a thermal belt is circulating, 

 and growth advances safely." 



