165 



Tjnent, produced but three and a half boxes of poorer oranges at the 

 same age. The former orchard is budded on sour stock, which, as 

 heretofore shown, roots deeplj', and it received a liberal amount of fer- 

 tilizers ; while the latter orchard is budded on the shallow-rootiug 

 sweet-stock, and received but a moderate amount of fertilizers. The 

 more productive of these two orchards evidently has the better root- 

 system ; it has also been ploughed deeply and irrigated in deep furrows 

 — therefore it never shows the need of water before the regular irri- 

 gation date comes around. On the other hand, the less productive or- 

 chard, which is on surface-rooting stock and has received much shal- 

 lower culture and watering, shows signs of drought before each irri- 

 gation date. In the case of orchards on the same stock, the value of 

 deep ploughing and deep irrigation is also very marked. 



Ihe So-Called " Hardpan." — The orange tree is a native of tropical 

 forests, where it obtains warm soil and abundant moisture within 

 easy reach. Its successful culture in countries like California, 

 which lack summer rains and moisture-laden atmosphere, is necessarily 

 to some degree artificial and a notable triumph of modern horticulture. 

 In order to achieve the highest results, it becomes more and more es- 

 sential that the grower shall keep the soil in the most perfect condi- 

 tion, shall apply all needed water and plant-food in sufficient but not 

 in excessive amounts, and shall pay especial attention to keeping the 

 feeding roots as low as practicable and to preventing the formation of 

 what is called "hard-pan," but is only the well-known " plough -sole," 

 aggravated by shallow irrigation. 



** Hardpan," some growers say, appears now where it was never be- 

 fore known. The fibrous roots of orange trees run along its surface, 

 and thus are subject to every vicissitude. It often happens that what 

 orchardists call '' hardpan" is only the firm layer of soil caused by uni- 

 form cultivation, or ploughing, wnether deep or shallow. The depth to 

 which soil is stirred should vary from year to year; eight inches, 

 twelve inches, ten inches, fourteen inches, and then eight inches again, 

 would put an end to much of the present outcry against "hardpan." 

 Cultivator teeth should also be kept sharp and should be "set down" to 

 various depths so as to prevent the formation of " plough-sole" of any 

 description, and to assist in breaking up that which former neglect has 

 caused. 



Yery few orange groves have been planted upon true "hardpan," 

 and if so planted have seldom succeeded. Only a few trees, such as 

 our native oaks, are capable of thrusting roots through the iron-like 

 layer of natural subsoil that is properly termed " hardpan." When 

 found to exist, it should be deemed sufficient to debar citrus culture, 

 unless so thin that, by boring or blasting, the root-system can be 

 established in good soil below the " hardpan," or when it is so consti- 

 tuted that when kept irrigated the roots will penetrate it. 



An instance of the latter occurred at Riverside, where Mr. Reed 

 planted a few trees on a terrace bordering on an arroyo, and found 

 what was reported as true " hardpan" near the surface. The trees re- 

 ceived " an abundance of water over the whole area for a year," and it 

 was then found that the roots had penetrated it to a considerable dis- 

 tance. 



