Owner: Bill Brush

Location: California, USA

Type of Operation: Walnuts and Almonds

Year We Visited Bill: 2012, as part of a USA Farm Study Tour

Walnut yield triples on the Albrecht-Kinsey system

USFDA declared walnuts a drug. That means growers etc. cannot claim they have health benefits. “Hey man, do you know where I can score an ounce of walnuts?”

Bill Brush’s 16 ha walnut ranch showed a big advantage for the Albrecht-Kinsey fertility system. The state average yield for walnuts is 5,600-6,700 kg/ha. Bill is consistently doing 17,900 kg/ha in his 12 yr crop.

Walnuts take 5 years to fruit and last for about 25 years, although better groves can go out to 40 years. The ranch we visited was deemed by the local university extension staff to be fit only for rice. Growers are paid $3.30/kg for the nuts, so the financial advantages of a high yield are considerable. Costs of bees is $750/ha, sprays, $500/ha, with total costs being $5,500.

Walnuts are grown on Black Walnut or Paradox root stocks, with Paradox proving better. Everything is irrigated as rainfall is only about 300 mm/annum, but the irrigation does have its drawbacks. One such problem is a trunk canker. One way of dealing with it is to soak a sack in a biological preparation, and wrap the sack around the canker. Insects move in and feed on the fungus, saving the tree. Another irritation is a husk fly that is dealt with by sprays.

Harvesting involves shaking, sweeping, picking up and washing, all completed in one day to avoid grading penalties. The hulls are high in Mn, B and K, so are recycled back to the orchard. Usually, grading and sale take a full 12 months. Upon removal of the crop, the wood is sold for firewood or chipped for ethanol production. Black Walnut trunks can be sold for $3-5,000 each for use as gun stocks.

Bill Bush Almonds

Walnuts on the programme produce 3 x the Californian average crop.

Almonds show the same results

Still on Bill’s land, but across the road, are almonds, almost ready for harvest. They are dearer to grow, with annual costs of $6,250/ha, and establishment costs of $12,500/ha. They take four years to fruit.

80% of the world’s almonds are produced in Central California where 283,000 ha are grown by 6,000 growers. California’s Central Valley mirrors that of a Mediterranean climate; cool, wet winters and warm, dry summers which are ideal for almond growth, provided the almond trees have access to water. Almonds are watered on a 14 day flood rotation, with the trees needing 270 litres per day, (walnuts use 450 l/day).

The blossoms of all California almond varieties are self-incompatible, requiring cross-pollination with other varieties to produce a crop. The single most important factor determining a good yield is pollination during the bloom period. More than a million colonies of honey bees are placed in Californian orchards (5 hives/ha) at the beginning of the bloom period to pollinate the crop.

The crop is harvested by shaking. The nuts are raked into windrows and allowed to dry, which can take from a few days up to two weeks. Pickup machines sweep the windrows into trailers for transportation to the huller. With the large crops of recent years, it has become more and more common for almonds to be stockpiled, either in the orchard or at the hullers. Hulled and shelled nuts are then transported to processing facilities, where they are stored pending further processing.

Bill Brush's almonds are also on the programme with similar results to the walnuts.

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