Growing Mushrooms on Local Agricultural Byproducts

Growing Mushrooms on Local Agricultural Byproducts

Summary

The first year of our grant was a successful and interesting learning experience which also produced a significant amount of grain and mushroom substrate. We were able to follow through on many of our proposals and goals, though as is often the case, we also had to modify our project due to our experiences and observations and due to the circumstances that arose over the course of the year. First of all, Jake Johannes was unable to plant sunflowers and so declined to participate in the growing part of the project, though he remains open to allowing the use of his mill for dehulling them.

This has been a blessing in disguise because Mark planted .63 acres of sunflower on his land and Conor’s land and learned a lot about the life of the sunflower.  Jake’s goal was to harvest sunflower for kernel and substrate, but for the purposes of growing mushrooms we primarily desire the sunflower hull and shell. So, after taking the sunflower planting on, and observing pest pressure and the inability of the sunflower to dry adequately in the field, we adjusted our strategy. We discovered that if we harvest the sunflower head early, then the kernel is only partially formed.  We eliminated the need for milling.  However, since we want to avoid using the kernel because it is unsuitable for substrate as it is high in oil and protein we will run the whole shell through a chipper/shredder and float the kernel off, reserving the hull for animal feed. We made 4 plantings of sunflower totaling .63 acres.  Planting 4 was planted the third week of July, too late to mature and were froze before the heads matured.  Planting 4 was sown in dry soil and during a rainless period.  It took 3 weeks to sprout further setting it back.  Next year we will irrigate when necessary to initiate sprouting on late planted fields.  Our calculations below are based on plantings 1, 2, and 3 and total .42 acres.  

Things we learned about growing sunflowers:

– Sunflower is easier to grow to a mature state than corn; it grew well on less fertile soil and responded well to drier conditions
– It outcompeted weeds better than corn.  Planting 1 and 2 were cultivated better than 3 but 3 outgrew even red rooted pigweed and grasses and looked and yielded just like 1 and 2.
– When planted too thickly, it still produced a good crop where as our corn suffered from plantings that were sown too thickly.  
-Sunflower heads are easier to harvest than corn ears, from a manual harvest perspective.
-Sunflower heads turn upside down as they mature forming a sort of bowl. Under extreme rain conditions some of them rotted from standing rainwater, which is probably another reason confectionary sunflower is grown in western Kansas where it rains less.
-Biggest insect problems were from corn earworm.  We were told by locals that weevils were a problem but we saw no damage.  Cucumber beetles were a minor problem on earlier plantings at flower stage. Insect damage rendered the sunflowers unusable for human consumption without a very intensive sorting process. 
-There are 4 parts to the seed head.  The kernel is wrapped in the shell, the shell is nestled in the hull, and the whole thing is mounted on the backing or the seed head.  As we extracted shell, the hull comes off too and looks to be good substrate that will add extra weight.

For the corn we proceeded mostly as planned, making our first planting in late March and sowing through June in several fields for a total of 3.04 acres (1^st planting- 0.4 acres, .08 of which produced successfully, 2^nd planting- 1.2 acres, 3^rd planting 0.6 acres, 4^th planting- 0.8 acres, 5^th planting 0.4 acres). We trialed 4 types of corn, a hybrid rated for high drought tolerance from Welter Seed, Bloody Butcher (a red OP variety), Black Aztec (a blue OP variety), and Green Oaxacan (a green OP variety). Bloody butcher produced well at 112 bushels/acre, while the other two OP varieties were planted in areas with intense weed pressure which combined with early season drought to create a crop failure. So far, the Welter hybrid has yielded an estimated 90 bushels/acre on somewhat less favorable ground that is being transitioned to organic and is low in organic matter and, we suspect, nitrogen. While this would be considered a low yield, as of the time of writing, we are over halfway finished with picking the corn and have only shelled around 25 bushels. We saved 16 of this as food grade corn and have been milling it into cornmeal for sale. This is helping to get the full value out of the corn and help make it economical to grow. We have determined with the corn shelled so far that about 1/3 of full corn ear is cob and 2/3 is seed, by volume. We have yet to begin trialing corn but will begin in the first weeks of 2015 with the program outlined below. Since the corn yields have varied considerably even within each field planted and because we have only shelled a small portion of our corn harvest, we will wait to estimate the cost of corn cob as a substrate until we are finished harvesting and processing. Still given the decent yields of the successful fields of corn we grew and the ability to mill and sell relatively high value corn meal, the corn cob can be viewed as a true byproduct substrate, as opposed to the sunflower shell which we are harvesting at this point only for use as substrate and which must be cheaper and easier to grow and harvest.

Objectives/Performance Targets

In early 2015 we will begin trialing the 4 types of substrate (chipped sunflower, whole sunflower, red corn cob, yellow corn cob) with mushroom varieties, most likely a chosen Oyster variety and Shiitake.

The Trials

Trial Design-
Constants: 1. Organism 2. Spawn- same type (ryeberries) 3. Same sterilization date 4. Same amount of spawn as inoculant 5. Run together as a group during the incubation and fruiting stages

Record: -Growth of bags at 5 days, 10 days
-Date it goes into fruiting room
-Harvest

10 Bags of each substrate type- 70% sunflower substrate whole/30% sawdust
-70% Sunflower substrate chipped/ 30% sawdust
– 70% Colorado shell milled/ 30% sawdust
– 70% white corn cob chipped/ 30% sawdust
– 70% red corn cob chipped/ 30% sawdust
– 40% Sunflower substrate whole/ 40% corn chipped/ 20% sawdust

Plans for 2015 growing season-

-We plant to grow up to 3 acres of sunflower in 2015.  
-Pick sunflowers at 85-90 days, minimizing kernel development.  
-Find a better way to extract the shell and hull
-Improve sunflower growing and harvesting method, therefore reducing cost of substrate
-Plant 2-3 acres corn, trialling new OP varieties and increasing the amount of Bloody Butcher planted
-Increase food-safe storage capabilities and improve processing facilities for corn

Accomplishments/Milestones

Cost of Sunflower Substrate:

Total hours spent- Planting/ Cultivating, Harvesting flower heads, extracting shell and hull, discing fields and planting cover crop- 58 hours x $10 per hour= $580, Seed: $95; Total cost: $675

Expected yield 1800 lbs per acre (shell and kernel)

756 lbs per .42 acre or 89 cents per pound

Our yield of sunflower substrate was 1160 lbs per .42 acres or 58 cents per pound

Our yield of corn so far is ~130 bushels with ½ of the crop (1.62 acres) harvested, including .32 acres of failed crop.

Our rate of corn harvest has averaged 3.6 bushels per hour, with 36.1 hours total spent harvesting corn.

We have been able to sell packaged cornmeal for $1-2 a lb., making the potential value of a cleaned and properly stored bushel of corn to $55-110.

Poultry feed is also being replaced, with corn making up 1/3 of our poultry rations.

Impacts and Contributions/Outcomes

Comparison Cost of other products:
Sunflower Shell Waste from Colorado: 20 cents per pound
Cotton Seed Hull: 35 cents per pound
Buckwheat Hull: 75 cents per pound
Rice Hull: 22 cents per pound
Soy Bean Hull: 16-32 cents per pound

Corn cob: price comparison not yet available.

After one growing season, we have decided it is too difficult to grow confectionary sunflower organically and harvest and mill the seeds to obtain an end product of sunflower kernels. The kernel is too easily damaged by bugs or the weather rendering it unusable, and food-grade storage of sunflowers is a greater obstacle than with corn and other grains because of the moisture content of sunflowers and their susceptability to rot while drying on the plant, prohibiting field-drying to the extent neccessary. Thus, we aren’t going to grow sunflower kernel for human consumption.

We were told by a neighboring farmer who has grown sunflowers to plant after July 1st to avoid weevils but since we don’t care about saving the kernel, we plan on planting as early as possible next year.  Since we are harvesting by hand, it would be better to stretch the harvest out instead of having one big harvest.  This increases the amount of time that we could have our own sunflower substrate.  We will plant from the end of April, or when the soil warms up, through the 3rd week of July and harvest from the 1st of August through Mid November.  Since we are not milling we still have kernel in the substrate.  We are going to run the sunflower substrate through a chipper shredder to mimic the milling process freeing up the kernel.  We then float the chipped sunflower substrate, most of the kernel sinks to the bottom. What floats is skimmed off and used as substrate.  The water is discarded and the sunken kernels can be fed to our chickens, geese, ducks, and pigs.  We do the same process for the Colorado shell because there is significant kernel still in the waste.  So instead of milling the kernel and selling it as human food, we propose to utilize it for our livestock.  The savings in animal feed could be added to the equation bringing down the 58 cents per pound.  The Colorado shell is cheaper but it is sprayed with conventional pesticides and each tote looks different, some properly milled, some more dusty and whole shell.  So our own sunflower substrate could hopefully be a cleaner, more consistent, and predictable product.

In regards to corn and corn cobs substrate, we have learned a good deal and will now focus on getting better at growing, cultivating, and harvesting on the cob’s potential as a substrate. Corn has proven to be more picky about growing conditions and produced much better when planted on Wakarusa Valley Farm’s well-worked, fertile, weed-free fields which have been farmed organically for decades. In some of Wakarusa Valley Farms’ fields which had laid fallow a year or two with now cover crop, crabgrass choked out young corn plants and was difficult to weed, resulting in total crop failure of 2 small plantings. Thus we will need to plan our corn fields well, planting corn only after nitrogen fixing and weed suppressing cover crops and fertilizing it adequately. We have just in the past couple weeks gathered all the equipment we need to quickly shell corn, but the grain cleaning process could still be streamlined considerably. For now, we plan on picking corn by hand for the next season, though we would not rule out an affordable, functioning 1 row corn picker if we could find one.

When we begin trialing the corn and comparing it to our typical substrate mix and the corn cob mix, we will get a better picture of its potential as a mushroom substrate. We are hoping, as some studies have indicated, that shiitake will grow well on a substrate partially made up of corn cob. Shiitake typically requires a substantial amount of wood (>=70%), which is more difficult and time-consuming to obtain than the sunflower shells from Colorado have been in recent years. For oysters, corn cobs could also be a valuable additive to the sunflower-based substrate which we have found oysters to grow very well on.

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