grass-fed beef, pastured pork

Bamboo Yield

For those of you who may not be familiar with the term, “bro science,” is when a dude (it’s always a dude) makes a few casual observations about a phenomenon and then launches into sweeping generalizations he proclaims loudly, widely, and authoritatively. When Garth and I run experiments on the farm we generally refer to them as “cowbro science” because we’re both well aware that with our work lives centered on taking care of animals and running a marketing/distribution business we have neither the time nor attention to develop powerful hypotheses and test them rigorously.  The fact that we actually are brothers and cow handlers makes it all that much better. Gently mocking ourselves helps us keep our “findings” in perspective.

With that disclaimer in place, our longest running agricultural experiment actually shows some promise. If you’re new to the blog or just skipped the boring screeds I wrote about my bamboo patch you can find the back story here, and here. The rest of this post will make more sense if you read those two old pieces first. The short version is we’re trying to develop a way to save money on our grass-fed beef and grass-fed lamb operation. Cows eat a lot and feeding them is one of our big expenses. Reducing the cost of winter feeding will allow us to keep our prices as low as possible.

Last week I completely defoliated 100 square feet of bamboo. The leaves and twigs came in at 33 lbs green weight. Multiply that by 432 (the number of 100 ft sections in an acre) and the total wet yield for an acre of bamboo forage near the end of the growing season is 14,256 lbs, or about 7 tons. Of course we farmers want to compare apples to apples and the only way to do that is on a dry matter (DM) basis. I sent a sample of leaves to DairyOne for analysis right after defoliating the plants and the DM composed 47.5% of the weight I picked. So… 14,256 lbs x 0.475 = 6,771.6 lbs, or a little less than 3.5 tons/acre of actual yield.

For comparison’s sake I asked my neighbor how many tons of hay he takes off his field since the soil is identical to the bamboo patch. He gets about 2.5 tons/acre of high quality hay per year.

Hay and standing bamboo forage are not precisely equivalent, but for my purposes they’re close enough to draw meaningful conclusions. Both will keep my animals well fed through the winter. If I can get a roughly equivalent yield/acre/year I’ll be many dollars ahead. Making hay requires diesel fuel, expensive machinery, and a lot of labor. Feeding standing forage requires an order of magnitude less capital investment (fences and water vs tractors and fuel). Strip grazing livestock requires time to set up and take down portable fences, but feeding hay does too (staging bales, cutting off the twine, giving the animals access to the bales, hauling manure if the bales are all fed in the same spot for a whole winter, etc). Between making hay and then feeding it out again the labor demand for strip grazing is many hours less than for an equivalent mass of hay. The hay my neighbor puts up has more feed value than bamboo leaves, so it has an advantage there, but because of all the other points in its favor I expect bamboo to save us a substantial amount of money over the long haul once I get a big enough stand going to support my cattle into the winter.

Over the course of this growing season I observed the bamboo stand more closely than in past years. The growth pattern of bamboo is distinctly different from the ‘normal’ cool season pasture grasses such as orchard, fescue, timothy, and brome growing on my farm. A typical cool season grass growth curve starts slowly in April, gradually ramping up until sometime in June, and then tapers back off. As the total mass of plant matter accumulates into summer the quality of the forage declines precipitously.

Image result for pasture quality and yield

By either grazing or cutting hay a few times the growth curve can be reset and quality will remain fairly good across the entire growing season. If the field is not mowed, trampled, or bitten, mass continues to accumulate but at a slow rate and quality of feed drops to a very low point. The goal of a competent grazier (one who manages grazing animals) is to rotate his animals in such as way that they’re usually eating pasture somewhere near the intersection of these two trend lines.

If I were to fallow a field for an entire growing season and then use it as stockpile it would look like this.

Foreground fallowed for the entire growing season. Across the road is the neighbor’s soybean field.

This field is out to the right of the end point on the lines in the schematic above. It is past the “Seed Ripe” stage of grasses. Note all the brown leaves and stems. There is plenty of biomass standing in a field like this, but there is not much worth eating even for an easy fleshing cow. The standard prescription for winter stockpiling of good quality pasture therefore is to try to graze two or three times by the middle of August and then rest as much of the farm as possible, allowing the pasture to “stockpile” for winter. Cold weather and lack of sun shut down most plant growth by mid-October in central New York, so working back about sixty days (a good middle-of-the-road amount of time to strike a balance between quality and yield) puts us around August 15th for the start of pasture stockpiling. Describing the timing of things and making it happen in anything but a perfect year are two entirely different beasts though. Rain, temperatures through the season, number of cattle, stocking rate in pounds per acre, fertilization or lack thereof, number of grazing taken during the season, and grass/legume/forb composition are all variables at play. It can be quite a challenge to get everything to line up just right, and here is where I am optimistic bamboo will make for good winter forage. Rather than flushing suddenly in the spring and then senescening into brown straw-like feed bamboo grows slowly and steadily all season long. It pushes new leaves from its twigs continuously through the growing season, building leaf mass in a nearly linear manner through the summer and fall. The newest October leaves and the oldest leaves pushed in June all go into winter looking green and nutritious. If it works it will make for a very simple management plan – graze once with sheep in the spring to stunt competing grasses and then stay off the bamboo stand all summer and fall. Once winter hits I’ll simply strip graze the bamboo stand a single time. The timing is fortuitous since we run our cattle and sheep together most of the year, but separate them during lambing, which will coincide with “weeding” the bamboo stand in the spring.

Pushing new culms even in October! The center cane has no branchlets yet as it’s still going upward. That’s a first we’ve seen of late in the year new canes.

Potential yield was the final large stumbling block that could have derailed this particular cowbro experiment. Now our next step is to get bamboo growing on a full acre of ground so we can figure out best management practices for how to utilize it in on our farm. Stay tuned for future updates!


Photo Credits – Edmund Brown



Edmund BrownBamboo Yield

Comments 4

  1. Jen B

    Thank you for the update on this project. I’ve been wondering how it was working out since you first introduced the idea. Yay for Cowbro science!

    1. Louise Calderwood

      Hi Folks: I like the bamboo idea. I have two questions:

      1. What is the TDN or NeL on the various bamboo samples?
      2. What is the water requirement for bamboo compared to the traditional cool season grasses in your region?


      1. Post
        Edmund Brown

        Hi Louise,

        TDN – 56. NeL 0.49. Clearly it’s not finishing feed or anywhere near dairy quality hay. But it should have enough oomph to keep an easy fleshing beef cow ticking along.

        I have no idea about water requirements. I’m lucky to live in a part of the world that almost always has plentiful rain. I haven’t been through a serious drought since I planted it. Last year much of NY state had a bad drought, but I lucked out and got rain when I needed it every time. This year it got hotter and drier than normal from the end of August through the middle of October. The pasture put on less growth than it otherwise could have because of the lack of rain. The bamboo kept on pushing new leaves at the same rate… but that doesn’t mean much since I didn’t measure anything precisely.

  2. Don

    It is truly amazing that bamboo has not had a lot more interest and agricultural production than it has. Think of it more like producing an evergreen grass plant that puts most of its mass under the ground, making it extremely more productive up above. It is similar to considering how many more people can live in skyscrapers on Manhattan Island as opposed to a typical suburban development layout. Bamboo are the skyscrapers of the grass world! Just like grass you find in pastures, some are “clumpers” and some are runners. There are well over 1500 unique species in the natural world and a relatively large, but much smaller variety that you can obtain in the USA. Depending on where you live, there are some that can be grown in cold areas of the country. Many will vary in height and grow less tall the more north you are located.

    We live in Zone 5 and have a collection of various bamboo. It is a surprising and interesting plant. One third of all homes in the world are built from bamboo. It is the fastest growing plant in the world they say. (However, as a side note, we also have the fastest growing biomass plant which is not a bamboo). One variety of bamboo we have will grow leaves in a spiral pattern. It does not even look like bamboo as most people would assume. We have one that has a palmate leaf pattern like a palm. (We are also slowly working on growing two true palms – that are the most cold hardy.) One has a lateral branch pattern that makes it look more like a “normal” tree. We have a dwarf variety. We have a potential larger lumber size that does well in low humidity areas. Another has hollow roots so it can carry oxygen into its roots in high humidity areas. One has solid canes that supplied the millions of arrow shafts in the past. One has bright yellow canes for decorative effects. One is the fastest growing variety and one has the largest leaves that will grow up to one foot or more in length and looks like corn (another famous grass!). We recently started an additional variety noted as the most edible for human use – the sweetest shoots and leaves for tea. All of this in Zone 5. It is an extremely successful plant. Some say it is an invasive plant but it does not fit the definition technically speaking. Containment strategies vary but must be a part of your planning for growing bamboo. It is increasingly being banned throughout suburbia. Its greatest mass is under the ground in the root system. This makes it an excellent choice for carbon sequestration, gray water, erosion control, buffer zones or bio-remediation projects.

    If anyone is seriously interested in learning more by seeing our collection here in Northeast PA, contact us by email and we will consider your request and get back to you.

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