[Illustration: FIG. 37--BURBANK PLUMS ON UPRIGHT CORDONS TRAINED TO TRELLIS]
Plums are seldom--almost never--propagated as horizontal cordons. I have never yet undertaken it myself, but propose to do so at the first opportunity and with some expectation of moderate success with certain varieties. The slow growing sorts like Green Gage, Italian Prune, and Agen seem to offer special promise.
In the form of espaliers plums are often trained against walls. Indeed this is the favorite way of producing fancy plums in England, and the same practise prevails to a considerable extent on the continent of Europe. In this country walls are not required, and in most cases would be of no advantage. Where it is desired to cover back fences or sides of buildings, however, plum trees in espalier form can be confidently recommended. The Domestica varieties of highest quality such as Bavay, Jefferson, Victoria, Pond, Bradshaw, and Coe's Golden Drop would have first choice. The Japanese varieties can also be grown on trellises or walls, but the freer forms, such as the fan espalier used for the peach, are better suited to their habits of growth.
The following varieties of plums can be recommended for dwarf bush forms:
Green Gage Jefferson Bradshaw Agen Grand Duke Bavay (Reine Claude) McLaughlin Pond Bleeker Italian Prune Cluster Damson (or other Damsons)
Such varieties of the Japanese class as Abundance, Chabot, Red June, Satsuma, Burbank may be grown on dwarf stocks in bush forms, but they are not altogether satisfactory. There are two objections against them: (1) It is difficult to keep them in restricted bounds, such a result being dependent on constant and severe heading in. (2) They overgrow the dwarf stocks very strongly and thus do not have a very firm hold on the ground. They are apt to blow over or break off after a few years, unless carefully staked up.
The following varieties can be recommended for upright cordons, in which form they will give moderate success if properly managed:
Coe's Golden Drop Agen Victoria Grand Duke Abundance Burbank Bradshaw Bavay Lombard Chabot Cheney Aubert (Yellow Egg or Magnum Bonum)
Also most of the clean-growing Americana varieties such as Smith, Terry, Stoddard, etc.