Studien uber die Frei-machung an 27 jahrigen Birnen- und Apfelbusch-baumen
Gartenbauwiss 10(5/6): 610-650
In a comprehensive study of 27-yr.-old apple on Paradise roots, and pear trees on quince roots, from 3 orchards, which had become established on their own roots, no relation was found between the compatibility of stock and scion and the amt. of own-rooting of the scion. Although it is commonly thought that the contact of the scion variety with the soil is the cause of scion rooting, yet such contact cannot be taken as the sole cause for own-rooting of the scion, because deeply planted trees, with the scion in contact with soil, were much more commonly met with than own-rooted trees. Own-rooting varied greatly with vars. and with individual trees, not leading, as desired, to great uniformity of the planting. Scion rooting is a varietal and individual tree characteristic rather than a general phenomenon. So far, no definite superiority of orchards on their own roots could be shown over orchards on clonal roots, because up to the present it has not been possible to establish a whole planting completely and at one time on its own roots.