Page:Popular Science Monthly Volume 67.djvu/343

Rh, necessary to combine in one plant both these negative characteristics, something that experience has shown can be done. However easily this is explained, still it elicits astonishment and wonder to see a cactus without spines. All that is now left to be done is the crossing with forms known as the most nutritious, and at the same time to watch the development of other characteristics, especially the root system. It will not take many years for Burbank's cactus to transform large stretches of desert into fertile fields even without irrigation.

Along the road in front of Burbank's house is a long row of high trees with wide spreading crowns and dark foliage. These are Burbank's first hybrids, walnuts, that are a combination of the eatable nut and an ornamental tree of the same genus (Juglans regia nigra). From seeds of this hybrid Burbank raised a few rows of seedlings which show a surprising variety in growth and leaves. These latter are all lanceolate, sometimes with broad leaflets, sometimes with narrow, some are petiolate, others sessile on the branchlets, now coarse and then fine, frequently reminding one of the common English walnut, and again approaching the ancestor, the black walnut. We saw some of the variety of forms resulting from crossing, and from these the best have to be selected for certain purposes.

Burbank's entire garden contains only two and a half acres, while the experiment farm near Sebastopol, about one hour's drive from Santa Bosa, comprises twenty acres. Two days each week Burbank spends on the farm, riding there on his bicycle; the rest of the week he is at home. Here are all the more delicate crossings, and it is here every new experiment is started. It is only when certain definite results are in view and when the cultivation of thousands of specimens is required that they are raised on the farm near Sebastopol.

He showed us a bed of wild flowers in his garden. He collects these in the vicinity, transplants them, selects and crosses the various forms as soon as they promise anything of advantage. Others he crosses with cultivated species of sufficient relationship. His idea in doing this is to make a large number of garden plants, which will be so fertile, and consequently so cheap as to come within the reach of any one. Briefly, he wants to spread over every garden spot in California a still richer treasure of flowers than it already possesses. Thus, for instance, he has crossed the large and deliciously night-scented Nicotiana affinis with the wild, tree-like Nicotiana glauca, which can not be called an ornamental plant on account of its greenish flowers, but by flowering profusely and by having such large bunches of flowers, it offers an excellent object for hybridization. We noticed several kinds of Cape gooseberries (Physalis), of the blood-red Heucheras and others already hybridized. The common garden poppy (Papaver somniferum) he had