- Author: Ben Faber
In a recent article in Fresh Plaza, the flood of imported jackfruit is reported. As recently as 2 years ago, I saw jackfruit advertized on Amazon for nearly $10 a pound. These babies regularly weigh in at 10-20 pounds. In their homeland, they regularly clock in at 80 pounds and more. I've recently seen fruit sold locally at Vons, Sprouts and Whole Foods for $4 for 20 pound beasts. That's still a hefty return. I saw the same fruit in the same stores for weeks on end. No body was willing to buy it. It was fruit imported from Mexico. I've seen similar fruit at the local swap meet where it's sold by the piece for $2 a pound. Still a nice price. Jackfruit can be grown in Southern California and until recently, a small grower could make a nice amount of money on the sale of the fruit. But as this article reports, at 28 cents a pound its hard to make money. We can grow it, but someone can always grow it more cheaply it seems
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Influx of jackfruit into US market
https://www.freshplaza.com/article/9113152/influx-of-jackfruit-into-us-market/
There is plenty of jackfruit available in the US right now as peak season continues in the Mexican growing regions. Over the past month, the market has become saturated with fruit leading to a wide range in prices and also quality. The peak of the season occurs in May and June so there is still several weeks to go until the market starts returning to normal.
"There is lots of jackfruit saturating the market right now," said Scott Miller of LA-based Tropic Trading Co. "We source them from Nayarit and are currently in the middle of peak season. There is all kinds of quality out there and prices have been all over the place, anywhere from between 28c per lb to 40c per lb."
Miller added that demand drops as summer progresses due to the presence of other fruit. "Demand usually drops in the peak summer months because there are so many other fruits available," he said. "People do eat jackfruit year-round but especially in California, there are a lot of stone fruit and other summer fruits that vie for consumers' attention."
Photos: Jackfruit interior and a tree growing in Long Beach
/h1>![jackfruit slice jackfruit slice](/blogs/blogcore/blogfiles/60981.jpg)
![jackfruit long beach jackfruit long beach](/blogs/blogcore/blogfiles/60982.jpg)
- Author: Ben Faber
Nitrogen and its Effect on the Balance of Vegetative and Reproductive Growth
With the big avocado crop out there, the question came up about whether a grower should add extra nitrogen to encourage more canopy growth to protect the fruit from sunburn or whether that would cause the fruit to drop. There is in our understanding the idea that there is a competition for resources and that in that competition one must best another. A commonly held belief is that if you apply nitrogen at the wrong time it will push resources to vegetative growth at the expense of fruit. This is somewhat true for annual plants that get most of their nutrients from outside sources (soil, air, fertilizer, water), but trees have a huge buffer in their storage organs (roots, stems, leaves, etc.). Most growth in trees occurs from this storage source and most importantly from photosynthesis and the sun. The more sun captured the more energy for flowering and fruit production.
So it is this competition for photosynthates that becomes the most limiting factor. When there is not enough to go around, the tree sheds fruit. If you see fruit dropping off a tree after applying a slug of fertilizer, it's a salt effect. Too much salt and it causes a water competition and the tree is stressed. It's not the nitrogen, but too much salt. With fertigation this is not so likely to happen as when dry fertilizers were applied and someone got too aggressive with the application
In fact a dose of nitrogen fertilizer is a good idea at this time when there are lots of clusters of fruit. This can encourage a flush of leaves that will protect the fruit from sunburn and damage that would cause fruit to drop. Also at this time, persea mite has been building its population and is starting to cause leaf drop. A bit of nitrogen to encourage leaf replacement is a good approach to dealing with this mite damage.
For further reading about the competition between vegetative and reproductive growth as affected by nitrogen (or little affected in fruit trees by nitrogen), D.O. Huett wrote a wonderful review of past research on this topic:
http://www.publish.csiro.au/?act=view_file&file_id=AR9960047.pdf
![avocado fruit avocado fruit](/blogs/blogcore/blogfiles/31494.jpg)
- Author: Ben Faber
Nitrogen and its Effect on the Balance of Vegetative and Reproductive Growth
With the big avocado crop out there, the question came up about whether a grower should add extra nitrogen to encourage more canopy growth to protect the fruit from sunburn or whether that would cause the fruit to drop. There is in our understanding the idea that there is a competition for resources and that in that competition one must best another. A commonly held belief is that if you apply nitrogen at the wrong time it will push resources to vegetative growth at the expense of fruit. This is somewhat true for annual plants that get most of their nutrients from outside sources (soil, air, fertilizer, water), but trees have a huge buffer in their storage organs (roots, stems, leaves, etc.). Most growth in trees occurs from this storage source and most importantly from photosynthesis and the sun. The more sun captured the more energy for flowering and fruit production.
So it is this competition for photosynthates that becomes the most limiting factor. When there is not enough to go around, the tree sheds fruit. If you see fruit dropping off a tree after applying a slug of fertilizer, it's a salt effect. Too much salt and it causes a water competition and the tree is stressed. It's not the nitrogen, but too much salt. With fertigation this is not so likely to happen as when dry fertilizers were applied and someone got too aggressive with the application
In fact a dose of nitrogen fertilizer is a good idea at this time when there are lots of clusters of fruit. This can encourage a flush of leaves that will protect the fruit from sunburn and damage that would cause fruit to drop. Also at this time, persea mite has been building its population and is starting to cause leaf drop. A bit of nitrogen to encourage leaf replacement is a good approach to dealing with this mite damage.
For further reading about the competition between vegetative and reproductive growth as affected by nitrogen (or little affected in fruit trees by nitrogen), D.O. Huett wrote a wonderful review of past research on this topic:
http://www.publish.csiro.au/?act=view_file&file_id=AR9960047.pdf
![avocado fruit avocado fruit](/blogs/blogcore/blogfiles/31737.jpg)
- Author: Chris McDonald
It is weed season! There is a principle in weed management that weeds are often better competitors for resources. Competition begins as soon as seeds break dormancy. The seeds that germinate first are often the ones that obtain the most resources.
Most plants have developed deep roots before they are a few inches tall (Figs. 1 and 2). Growing beans in a paper towel will highlight this point, the plant will be many times deeper than it is tall. What this means for plant competition is that if there is a plant that germinates quickly and one that germinates slowly, the slow plant will be at a competitive disadvantage.
Fig. 1 a (left) carrot root after 47 days (Weaver and Bruner 1927). Note: Each square is one foot. Fig. 1b (right) Horned Spurge (Euphorbia brachycera, a perennial) root habit. The plant on the left was growing in the Great Plains of Colorado. The plant on the right was growing on a "half-gravel slide" in the Rocky Mountains of Colorado (Weaver and Bruner 1927). Note: Each square is 1 ft. The roots on the left plant are over 7 ft. long.
Fig. 2. Rooting depth of Sorghum A35/RQL12. Note: Leaf 2 is the stage of growth when the plant has 2 leaves, leaf 3 has 3 leaves. Total length at the 4th leaf stage is approx. 60 cm. The grid pattern in leaf 4, 5, 6 is an artifact of washing methods (Singh et al. 2008).
Many studies have looked at the effects of weed competition on crops. Researchers have even developed multiple tools to help growers estimate the most effective timing of herbicide application in relationship to the loss in yield a grower is willing to tolerate. For example, if the grower will tolerate a 5% loss in yield due to weed competition vs. a 10% loss in yield, she will be spraying much sooner in the 5% loss situation than the 10% loss situation. In many cases the threshold for yield loss is reached when the crop has only 2-5 leaves (in corn, see Fig. 3 below). The main point from these studies is that optimal weed control often occurs when the plants are young, because plants are always competing for resources.
This basic principle occurs in wildlands too. Many weeds outcompete native plants simply by germinating first. Those seeds that germinate first then usually start to use resources (water and nutrients) in the soil first and become well established. Notable weeds that germinate with fall rains are storkbill, annual grasses, like bromes, oats ,wild barley and others, as well as thistles. Some native plants will germinate as soon as the weeds, fiddleneck is one, but other native plants germinate more slowly. Partly because their germination is cued to wait for a large rainstorm when the chance of surviving to reproduction is high. In some years weeds will germinate with a small storm in October and if there is a large and early winter drought they will die by January. The slower germinating natives will not have germinated at all.
There is a lot of complexity in regards to which plants will become the most competitive or problematic for the landowner between seedling establishment and flowering. The main point is the race starts as soon as the soil is wet and seeds germinate. Most often weeds grow faster than native plants and keep racing ahead.
There are far fewer studies of the roots of weeds, as compared to crops. We can get an good idea of what the roots look like because of the groundbreaking work of John Weaver and William Bruner at Univ. of Nebraska. Weaver and Bruner observed a variety of field and vegetable crops and painstakingly dug the roots out of the soil using adjacent trenches (Weaver and Bruner 1926 and 1927). In general roots, especially when grown in good soil, are very long and very dense and often occupy a greater volume than the plant canopy.
Because we had a significant late-fall and winter storm, this season it appears that most weeds and natives are germinating at about the same time and the faster growing weeds will out compete the natives. In other years a small early storm can ‘flush out' weeds and preserve some, but certainly not all, native plants. Because of this precipitation pattern, ‘yield losses' in wildflowers could be high where weed populations are significant.
Fig. 3. Corn yield loss and the timing of weed management as it relates to fertilizer applications. Note: V1 is when 1 leaf is present, V2 is when 2 leaves are present, etc. In this model, to avoid losing 5% yield on an unfertilized or low fertilized field weed control will need to occur around the 2-3 leaf stage of the crop. Always consult a professional for personalized information.
- Author: Ben Faber
Along the coast, it is very common to see windbreaks protecting the citrus and avocado groves. Invariably the first two rows next to the eucalyptus trees are shorter and less thrifty than the citrus further away from the windbreak. This is due to competition primarily for water, but somewhat due to light, as well. Often by putting emitters on the windbreak, the completion stops. Growers will also root prune between the windbreak and the first row of citrus. Those roots inevitably grow back and pruning must be done again. This also occurs in areas where there are oak trees or other natives that are planted in or around the orchard. Growers will frequently plant right up to the canopy or even under the canopy of the native tree(s), with a similar result seen with windbreaks.
It is important to remember the architecture of roots. Not all trees are exactly alike, but a general rule of thumb is that the active roots go out one and half times the height of the tree. So a 40 foot tree will have competitive roots out 60 feet away from the trunk. That’s why it is best to keep a distance away from a competing tree, because avocados and citrus are just not as competitive as an oak or eucalyptus.
In low rainfall years, this competition is even more intense. Significant defoliation of the crop plant can be seen. The grower then thinks that it is some disease and ponders what to spray, when they should actually be spraying more water.
![windbreak windbreak](/blogs/blogcore/blogfiles/17137.png)