|
OBSERVATIONS FROM A GROVE OF HENON BAMBOO by Daphne Lewis, August, 2003 2003 is the eighth year that I have harvested shoots from two groves of Phyllostachys nigra henon in Kirkland, Washington. Both groves are hedges running east and west. The Driveway Grove measures 750 square feet; the North Grove measures 1200 square feet. Added together they approximate 2000 square feet or a twentieth of an acre. The Driveway Grove sits on the edge of the fill that makes the parking pad at the end of the Driveway. The parking pad is typical fill, ie., compacted mineral soil. The North Grove sits on native soil that was here when the house was built. Parts of it are moist year around. Yield from these two groves has varied over the years because of weather, thinning of culms, mulching and fertilizing. The groves have never been irrigated. We receive little rain during shooting season. During rhizome extension season, we get less than 3 inches of rain because July and August average less than an inch of rain each and September averages 2 inches. Since bamboo is a summer monsoon plant, it is a wonder that my groves yield at all. As the "Shoots per 1000 Square Feet" graph shows, the lowest yield was 37 pounds per 1000 square feet in 2000. The highest yield was 85 pounds per 1000 square feet in 1998. Thirty seven pounds is equivalent to 1600 pounds per acre. Eighty five pounds is equivalent to 3700 pounds per acre. In 2003 the Driveway Grove yielded 28 poles. The North Grove yielded 109 poles. A few more could have been taken from the Driveway Grove. Another 100 should be removed from the North Grove. The low back section is still only partially thinned and has mostly inch to an inch and a half in diameter poles. Since thinning is done by volunteers in work parties, we stop before the thinning is as complete as I would like. We had one work party for the Driveway Grove. These poles went to Carol Stangler's workshop at Boo Shoot Gardens. We had a second work party for the North Grove. The volunteers were bambuseros who wanted the experience of thinning a mature grove and wanted poles to take home. Each volunteer took 10 to 20 poles home with them for a total of 98 poles. Most were 14 to 16 feet to the second or third branch node. We decided to use only the branchless lower section and to take the leafy tops to the Zoo. This way we did not have to remove more than a few branches per pole. Milt and Sandy Bastian brought their farm truck pulling a huge trailer. They loaded the leafy tops of the poles into the trailer and took them to the elephants at the Zoo. The keepers told the Bastians that the elephants prefer the branches and leaves left on their poles. That way they can play with the poles. They like to throw them into the trees to knock down leaves to eat. (Yet another tool making animal?) A friend came to the grove in August and I cut another 11 poles for him. 1996 I partially thinned the Driveway Grove. The two groves differ from each other. Sections within
each grove also differ. Understanding these differences allows
for improved site planning for a bamboo farm. Observations on the Driveway Grove The Driveway Grove yielded more than the North Grove on a square foot basis for the first three years because it was thinned. It has the easiest truck access so that is where we began. We did not begin thinning the North Grove until 2000. The Driveway Grove has three sections: east end, middle and west end. The east end has full sun exposure to the north, east and south. It warms up faster than any section because the early morning sun hits it on its north edge during spring and summer. Later in the morning the sun veers around to warm its south edge. The warm east end shoots in spring before other parts of the grove and long before any section of the cold North Grove. The east end also finishes shooting quickly. The east end is relatively level so it is easy for me to put wheelbarrow loads of mulch on it. Because of its good sun exposure, well drained soil, and careful thinning, it has had larger culms than other sections of either grove for several years. The middle section grows on ground that slopes to the north. It begins shooting after the east section and continues over a longer period of time. In the last few years it has produced large culms. In 2003 the biggest new culms are in the middle section. Some of its newest culms are over 37 feet tall; older culms are 31 feet tall. The middle section produces more shoots than the other two sections. The west end is the poorest section. The ground slopes steeply to the north because of the truckloads of fill making the pad for the carport. The steepness of the fill makes it difficult to get mulch to stick to the slope. Everything rolls down and off the steep grade including moisture. In addition the west end is shaded by the adjacent carport to the south and the house to the west. The ground is colder by far than that in the middle and east sections. It takes at least a week longer to reach 60°F in May when shooting should begin than the other two sections. The west end of the Driveway Grove section produces fewer shoots and the culms are smaller than those in the middle and east section. Observations on the North Grove The North Grove runs east and west along the north property line. The ground slopes continually downwards from east to west following the original grade of the lot when bought in the 1950's. The neighbor's house behind the North Grove is built on fill. The fill edges the property line and makes a STEEP bank rising six foot behind the grove. The grove was planted to hide this wall of fill and the two story house set above it. The North Grove has five sections: east, middle, low back, south edge, and west. Each yields differently from the others. The east section is the high end of the North Grove. Its soil warms more quickly than the other sections except for the south edge which is the first to shoot. The south edge extends about four fifths the length of the grove and abuts a lush, ever moist lawn/meadow. The low back is behind the south edge and does not warm until harvest is over. A small drainage ditch separates it from the south edge and keeps it excessively moist. The west end is dry enough to warm during shooting season. The east section was thinned in 2000. You can see from the graph "Yield per 1000 Square Feet" that the yield of the North Grove leapt up in 2001. In 1999 the east section was mostly one inch poles quite close together. Now it consist of 2 inch poles spaced about two feet apart. In 2003 this section yielded many excellent shoots. It has nice culms well spaced. The east section is on higher ground than the rest of the North Grove. It receives sun from the north, east and south. Sun is partly blocked to the south-east by a giant fir tree. This section begins shooting a week or two after the Driveway Grove. The south edge faces a large, moist meadow. It is shaded from the north by the 3 story house behind it. This edge gets sun from the south all day but not the early sun that is behind the house. The soil is good organic loam. The south edge has not been completely thinned but is much improved. It produces well. The mid section is upland soil. It is shaded by the house to the north but gets good sun from the south. It produces erratically for reasons that I do not understand. It is not very productive and is taking years to fill in large gaps. This year I am finally getting wheel barrows of mulch to it. The low back is wet and dark. A little drain ditch with year around water divides this from the front edge. The soil is always damp and cold. The low back is shaded by the south edge in front of it and the house and bank of fill behind it. The thinning here has never been completed. Very few shoots appear here. It is an unproductive part of the grove. It is, however, a good source of one inch poles. The west end is upland soil again. The section is quite productive. It gets good sun from the south; little from the north because of the house and little from the west because of tall trees. Thinning is mostly complete but because it is farthest from the pile of grass clippings, the west end tends to get less mulch than other sections. Overall Observation Soil Temperature The earliest yields come from the warmest soil. Cold soils may not produce at all. Soils can be cold from too much soil moisture, too much slope away from the sun, or from too much shade from buildings and/or trees. My groves start shooting after the soil warms to 60°F, not before. The data in the chart below comes from 2002. I did not place my thermometers in 2003.
Save the First Big Shoots The biggest shoots tend to be the first ones to appear. Mark these big ones and let them grow into culms. The goal is to select the biggest and best shoots to grow up and become culms. The later shoots will probably be smaller than these first ones. Manage for Large Shoots Crowded groves produce small shoots. Open groves produce large ones. Small shoots come up where the grove is not mulched. Large shoots come up where the grove is mulched. The labor to harvest small shoots is as much as harvesting large ones. Manage for large shoots Crowded groves produce small shoots. Open groves produce large ones. Small shoots come up where the grove is not mulched. Large shoots come up where the grove is mulched. The labor to harvest small shoots is as much as harvesting large ones. Manage to produce large shoots. Bamboo Grass Once you start harvesting and managing a grove for shoots, the stumps of the harvested shoots produce lots of tiny branches. These become 2 to 3 foot "grass". Invariably the "grass" has bamboo mites. I think the mites ride to the ground on the falling, dead leaves. Then they climb to the "grass" with its fresh young leaves. If I were a farmer with my own land, I would raise chickens to harvest this grass. In my suburban and research situation, I cut the bamboo grass to ground level with hedge clippers. Why cut the "grass"? You need the grass to be gone so you can find the sprouting new shoots. Manage Your Buyer It is important to keep in touch with your buyer. Last year I sold my shoots to the Dahlia Lounge. I was received enthusiastically by the chefs when I showed up in the kitchen with my bucket of shoots. This year there were new chefs. They did not use all the shoots I brought. They said that with the economy down, customers were ordering a glass of wine and hors d'ouvres rather than a full meal. If I had called them after the first few deliveries to find out how how they were doing and to manage the shoot selling business, instead of coasting on the good will of the previous year, I would have known they were having trouble selling my shoots. I could have encouraged them to change their menu to sell more shoots. I could have brought them only what they needed. I could have arranged to sell the surplus to someone else. Now that I am fertilizing and mulching, my yields are increasing. Next year I plan to sell to an upscale grocer such as Whole Foods as well as to the restaurant. In the next few weeks, I will be contacting the produce buyers for them as well as talking with the chefs at the Dahlia Lounge. Scheduling of the Labor of Harvest I harvest shoots twice a week and arrange that schedule with my customers. Two times a week works well for maximizing yield while minimizing the time in the grove (and the long drive to the grove). I tried a once a week schedule but too many shoots became too old to harvest. I lost considerable poundage. Mulch Mulch works miracles. Large shoots of 1/2 to 1 pound grew where I had mulched with grass clippings. Small shoots of 1/4 to 1/2 pound grew where I did not. Chickens The bases of the cut shoots send up masses of small twiggy, leafy branches. These leaves hice new shoots until they are too old to harvest. They harbor mites. I cut the branches to the ground with hedge clippers before harvest begins. I also cut them many times throughout the summer. If I were a farmer I would run fowl in the groves as soon as harvest is over. It would be much easier with fowl scratching and eating the leaves (and mites) than bending over and cutting the “grass” with hedge clippers! And the chickens would stir the mulch and drop nitrogen pellets. Thinning Thinning out the old culms to make room for the new
ones is satisfying for several reasons. When I first arrive at the grove during shoot harvest, I walk through and tie with surveyor tape the shoots that I want to leave to grow into culms. I then harvest the unmarked ones. In July after shoot season is over, I return to the grove to thin out old culms. I look at each new, taped culm and take out old culms nearby that crowd it. I want each new culm to receive plenty of light to its leaves. That way each of its leaves photosynthesizes and each branch remains alive. Sometimes I take out one culm per new cane, but more often since my groves are still not perfectly thinned and the size of the new culms is increasing, I take out two to four canes per new culm. As the grove improves, the new culms are larger and need more room than smaller ones. The larger culms must be spaced farther apart than the smaller older culms. Yield Pattern The yield pattern graph shows a combined harvest period of one month (29 days). The Driveway Grove yielded in a bell curve. Its harvest lasted May 13 through June 6, 25 days. The North Grove yielded in two bell curves. The first peak was from the earlier warming section. The second peak was from the later section. Its harvest went from May 19 through June 10, 22 days. Red Rootlets At the base of a bamboo shoot are small, shiny red buttons. These are the tips of the roots that will grow to support the new culm. The growing tips are red; the young roots are white. I tasted a few when they were a half an inch long. They had no acridity and tasted very familiar, but I could not place the taste. I asked the chef at the Dahlia Lounge to taste them. She said they tasted like fresh sweet corn. The new roots taste not like bamboo shoots, but like tender sweet corn! How to Harvest This year I used a miniature pick ax to pull mulch away from the shoot. I used a sharp knife to cut the shoot. The knife was not as efficient as my previous method of using a spade for digging bulbs that I carefully sharpened like a knife. However there was no wastage when I used the knife and therefore no prep time. I eliminated a step by not having to prep each shoot. I always deliver to the restaurant with the shoot cleanly sliced and washed clean. Dollar Value I sold the shoots for $3 a pound. 138 pounds brought in $414. I cut 137 poles. Had I sold them at $5 per pole they would have been worth $685. Conclusion When choosing a site for growing bamboo shoots in the Pacific Northwest, choose:1. a warm site 2. a site with easy truck access. My yields would be greater if my site were uniformly as good as the better sections of my groves. A third of each grove produces little or no shoots. Download article as a PDF File
|
|
