“…if we find our Trees unruly or over luxurient, it is proper in [pear] Espaliers, to let a single Branch in the middle of every Tree grow up without Pruning, and as it rises above the Espalier let it make a stem of about two Foot, and then allow it to grow into a Head – from this way of Management the superfluous Juices in the Hedge-part of the Tree will be drawn off, and the Branches in that part will come to bearing much sooner than they would otherwise do, and, at the same time, the great Demand of Nourishment below will so model the upright Branch that it will come to bearing also; An Instance of this is at Cambden-House at Kensington, where I made the Experiment ten Years ago, and I am inform’d by some Persons of Quality, who are my Friends, that the Year, 1724, those Trees where so full of good Fruit, that they had not seen any thing of the same kind equal to them.“
R. Bradley, Ten Practical Discourses Concerning Earth and Water, Fire and Air as they Relate to the Growth of Plants, printed by J. Cluer and A. Campbell, for
B. Creake at the Bible in Jermyn-Street St. James’s, 1727.
The more I dip and delve into venerable fruit growing texts and tracts, the more fascinated I become with the historical development of the body of knowledge of fruit tree morphology and function. (It might not be particularly useful, but it’s interesting...)
In the early C18th most naturalists and pomologists were convinced that sap was the key to the health and wellbeing of a tree, in much the same way that earlier physicians had been convinced that the four humours were the key to the health and wellbeing of a human being. Much like the humours, superfluous volumes of sap were deemed unhealthy and unproductive, and so had to be drawn off, usually by pruning the tree’s limbs or roots, or manipulating it in some other manner.
With no knowledge of photosynthesis, the cellular structure of plant tissues and the role played by transpirational pull within their circulatory systems, our Mr Richard Bradley – the very first Professor of Botany at the University of Cambridge and author of several highly-regarded volumes on botany, so certainly no slouch in the scientific enquiry department – was rigorous in his observation of apparent cause and effect, but unable to make the connection between the leaves – the source of the additional photosynthates required to improve the tree’s fruit and provide enough energy for repeat fruit bud setting – that were allowed to develop on the Head of the espaliered tree and its bumper harvest. Likewise the existence of key phytohormones such as auxin, cytokinin and gibberellins – the interplay between them playing a key role in fruit development and tree morphology – which were still a century and a half away from being hypothesised, never mind identified.
But still, the Persons of Quality (who were his Friends!) were pleased with their pears, and at the end of the day it’s the result that counts.