De Crescenzi (c.1230 - c.1320) practiced as a layer from 1274 until 1300, during which time he traveled from city to city in the Lombard League. Traveling jurists were important, due to the concern that local lawyers would not be impartial. As he traveled, he took note of farming practices, comparing them to what he observed at the Dominican monastery in Bologna (his brother and several friends were members there, and its head was his confidant).
He retired at the age of 70 in c.1300 to his own farm in a suburb of Bologna. His application of efficient farming practices earned him such a reputation that King Charles II of Sicily asked him to write a treatise on the subject.
De Crescenzi produced the Liber ruralium commodorum ("Book of rural benefits") between 1304 and 1309, dedicated to Charles. It was so well received that Charles V of France ordered a French version in 1371. It was translated into Latin in 1471; 57 editions in different languages followed.
This was the first serious work on agronomy in a millennium, and borrowed heavily from the "lost" classical works on the subject. The structure is based on the De re rustica ("About rural things") of the 1st century Roman writer Columella, and De Crescenzi was clearly able to get a copy of the agricultural work of another Roman, Taurus Palladius, but he makes his own point in the introduction about soil that is fundamental to all farming:
The power of the soil should be investigated, and when it is discovered it is like an inestimable treasure that should be conserved with humility and patience.
He argued that a field giving poor yields should be left alone for four or five years until planted again. He recognized the need for crop rotation, "green manure" by plowing under what was growing wild, and regular fertilization—practices that make sense to us today, but that had fallen out of use for centuries.
The work is in 12 parts:
- Siting and layout of a manor, villa or farm, considering climate, winds, and water supply; also the duties of the head of the estate
- Botanical properties of plants and horticultural techniques
- Agriculture of cereals and building of a granary
- Vines and winemaking
- Arboriculture—trees useful for food and medicine
- Horticulture—plants useful for food and medicine
- Management of meadows and woodland
- Pleasure gardens
- Animal husbandry and bee keeping
- Hunting and fishing
- General summary
- Monthly calendar of tasks
You can see how extensive and thorough a guide for farming on a large and a household scale it is.
One of his emphases is on the utility of a particular plant, so I thought we'd talk next about its history and about what De Crescenzi has to say about it: the misnamed lupine.