North American Fruit Explorers mailing list at ibiblio

[Rondi <dee@mokalive.com>]

This technique comes out of the U of Arkansas and I am considering doing
some experimenting with this. Has anyone here tried this. I would be
interested in hearing about the results. I've noticed in the wild that it is
not uncommon for plums and wild cherries to grow in thickets and this method
kind of reminds me of this. I'd like to try this with some apricots and
peaches.

Rondi



http://www.uark.edu/depts/agripub/Publications/Agnews/agnews03-64.html


Arkansas peach production has a whole new look

Source: Curt Rom 
479-575-7434 
crom@uark.edu 
  
By P.J. Hirschey 
UA Department of Horticulture
phirsch@uark.edu 
Oct. 28, 2003 

FAYETTEVILLE --- Peaches have been cultivated around the world for
centuries. And for centuries, the technology used in their cultivation has
remained virtually unchanged. Until now.

Enter the Perpendicular V, a unique method of training commercial peach
orchards that has Arkansas peach growers all abuzz. It combines high density
planting with careful shaping and management of individual trees into a
system that holds the potential to transform the peach production industry.

"At the U of A, we have been testing potential new systems for 20 years. The
Perpendicular-V has emerged as the most useful," says UA horticulture
professor Curt Rom. Rom has spent more than ten years researching this
California-developed system at the UA Division of Agriculture's Fruit
Substation near Clarksville and adapting it for use by Arkansas peach
growers. 

"We have seen more than a 40 percent increase in total crop yield over a
10-year period using this system," he says. "Growers have responded very
enthusiastically. In all the things I've done, I have never seen growers
adopt a new technique this readily."

"Peach orchards have traditionally been planted at a density of about
110-150 trees per acre," Rom explains. "Youtypically get some yield by year
4 or 5 and achieve maximum production by year 9 or 10. However, the average
life of a peach orchard is only about 15 years before it begins to decline
and consumer preferences change. This means that growers are only producing
at maximum potential for about five years, which is not economically
efficient." 

In the Perpendicular V system, trees are planted at a density of 300-500 per
acre, trained to a specific "V" shape and kept to a height of only 9-12
feet. Growers generally get an economic crop by the third year and reach
maximum production by the fifth year, five years sooner than in traditional
systems and with a more efficient use of labor and equipment, Rom says.

Training a peach tree is a long-term process that begins at planting. It
involves pruning and spreading the tree into a desired shape as it grows.
The objectives of training are to achieve maximum health and productivity of
the plant. 

"The beauty of using the Perpendicular V technique is that it is a
grower-friendly system that takes advantage of some of the natural
characteristics of the tree," Rom explains.

When training a tree to this system, two branches are selected, one on each
side of the trunk, to serve as the main scaffolds. Smaller fruiting branches
are allowed to grow along the sides of these scaffolds, but the top sides of
the scaffolds are sheared of limbs to keep the center of the canopy
completely open. The resulting orchard rows have the overall appearance of a
large Y, with the main scaffolds becoming a "fruiting wall" on each side of
the row. 

This system allows maximum light penetration into the canopy, which, in
addition to increased overall productivity, also improves fruit color, size
and general quality, while helping to reduce fruit rot and disease.

"In a tree with a large, round canopy, light only penetrates to a depth of
approximately 1 meter," Rom says. "This means that the inside of the canopy
is basically wasted for fruit production. In the Perpendicular V system, we
have reduced the canopy volume, but significantly increased the surface
area. The growing surface is essentially two perpendicular planes that are
approximately one-half meter in depth, so light reaches every part of the
canopy. Since productivity in an orchard depends upon the efficiency of
light interception, this system is very productive."

The ability to capitalize on labor use is another advantage researchers have
found with this new system. The "Y" shape greatly simplifies pruning,
requiring less training for workers. The shorter tree reduces the need for
ladders in harvesting the fruit, while the high-density planting means that
workers can move from tree to tree in only a few steps. In Australia, some
orchards planted to the Perpendicular-V have even developed self-propelled
vehicles to use during harvest and pruning, which carry workers at a set
pace down each line of trees guided by an infrared light at the end of the
row. 

"The Perpendicular V system allows us to produce a commercial crop using
much more modern technology that has increased yields over the long term,
maximized labor efficiency and increased overall profit," Rom says.