Harvesting rhizomes

In late March we attempted to harvest rhizomes of some of the miscanthus plot. A patch of miscanthus was dug up in order to investigate the complexity, yield, and process of harvesting the rhizomes. Since this was a small scale effort, a Bobcat was used with a tine tooth bucket to dig a shallow trench along a row of miscanthus grass. The root balls fell out of the tines very easily. The effort was minimal thanks to the machinery used. Some were dug by hand and was a much more physical task that would be unreasonable in a large plot.

One small 10x10 foot area cleared for rhizome harvest

An example of a plant to be harvested. This was done in early spring but this past winter and spring have been very warm compared to normal and some growth has begun.

An area dug up

The tool used to dig up rhizomes

A rhizome pulled from the ground

All harvested rhizomes set out from where they were dug from

A collection of rhizomes dug up

Same group of rhizomes washed off.

Early spring

The spring season has started and it has been very unseasonably warm in western Iowa. As of March 30, new growth is visible above ground on many plants.

New growth on a plant as of March 30, 2012

A smaller plant beginning to grow again.

The total field at the start of spring

The total amount of biomass was not large enough to justify a harvest. The dormant biomass form the field will be left in the field as cover.

Small harvest

A small harvest was made in late winter of the miscanthus grass for analysis. There was a significant difference between the stem and the leaf portion of the grass. The stem was very stiff and long.The leaves were similar to more traditional grass and was loose and stringy. Harvesting the stems is most desirable, but might prove to be difficult.

The two pictures above are the harvested miscanthus stems

This container has the leaf portion of the harvested miscanthus

A small harvest

Back in November we were able to attend and present at the Small Farm Trade Show and Conference in Columbia, Missouri. This was a great experience and we were able to make an initial presentation on our project so far. We were able to also meet some very interesting people who are very concerned with the environment as well. I learned quite a bit about raised bed gardens and using humus to enhance soil. It really got me in the mood for making biochar. Then I met a researcher at the conference who was doing just that. John Topic had also won a grant through SARE and was researching improving soil by the use of biochar. Very interesting stuff and we hope to collaborate someday.

Following that not much to do on the farm but wait for the grass to dry out and drop the leaves. On December 28, 2011 I was able to go out to the field and try to hand harvest some of the plants. It was an unusually warm winter thus far, and not much had changed with the field since October.

Miscanthus field in late December

I used a rake to remove the weed grass that had now laid down nicely to reveal the miscanthus grass that was still standing tall.I got a spot about 15'x15' cleared out so I could harvest neatly without contamination of the other grasses.

Small cleared patch.

I used a corn knife to hand cut the miscanthus just above ground level. I took the plants whole in a bag back home. The biomass will need analysis for mineral and energy content.

Harvested bunch of miscanthus - single plant, first year

After I was complete, that left a fairly bare patch in the field.

So I raked the grass back into the spot to help prevent any soil erosion during next spring.

What I really found interesting with the miscanthus plants is the very different physical properties of the plant stems versus the leaves. The stems separated very easily from the rest of the plant. I assume this is what should happen after winter with leaves have fully dropped from the plants. We will have to wait to see what winter brings us in terms of snow to see if that is true or not in the spring. Also, this field is first year growth that is practically an unharvestable quantity. We will have to wait until next fall to determine the final weight and volume percentage of the harvested grass is leaves compared to stems.

Mid October

This post is for the end of season pictures I was able to get in mid October. Miscanthus is easy to spot as the foxtail had all died out. Many of the plants were doing really well, but the population of miscanthus plants was not what we had hoped it would be. This first season was a great learning experience. Basically no biomass to harvest this year, we hope to see a tremendous regrowth in the spring.

Ending of Summer

The miscanthus plot has been doing very well over the summer. Fairly frequent rains, good sunshine, and heat have all helped grow the biomass. The broad leaf plants are gone, but the foxtail grass still grew up with the Miscanthus. It is most likely competing for sunshine if anything. The root mass of the foxtail looks sililar to the miscanthus of a fair amount of grass "stalks" coming out of the same cluster. the ground is rather bare, very similar to a corn field, completely canopied by the grass leaves. We are happy with the first year results.

The next big task is determining how to dig up the rhizomes for later propagation next spring. Still in the plan for this fall is to watch the grass go dormant, and try and harvest some of the grass over the winter. We would like to plan a field day next spring depending on how this fall and winter ends up.

The miscanthus plot can be rowed somewhat for the plants that are taller than the other grass. 

We drove into the back of the field to get a look at the best stand in the plot. A picture of Denny here standing by a row of 1st year miscanthus.

Lots of other grass though...

I took a picture from the road to view the plot from a distance, it was a little too level between the two terraces to see much. 

Miscanthus learning event

We were invited to attend a field day just south of Greenfield at the Iowa State University Neely-Kinyon Research and Demonstration Farm in Adair county. There were several great topics on No-Till practices, cover crops, and miscanthus grass. Interesting to me the John Deere 2510H was exhibited for its low disturbance NH3 application. In a previous position as and engineer at John Deere, I had the opportunity to work on that machine when being first introduced to the market. The information is available at the Iowa learning farm website:
http://www.extension.iastate.edu/ilf/

We were able to speak a short bit about out experience of farming miscanthus, and it was great to see how interested the attendees were on the topic. 

There is also a like to a great Webinar on the site above by Emily Heaton from Iowa State University covering growing miscanthus grass as a dedicated bioenergy crop.

Lots of good sunshine, heat, and rain on the miscanthus plot. With the weeds knocked down, it is performing well. When we were at the field day mentioned above, it was great to see second year and first year miscanthus side-by-side. Sadly, my camera only saved blank images when I was there, so none to post today. It was good to see how our plants compare - they look like great first year plants. All we can expect now is for the plants to continue to do well, go dormant well in the fall, and really produce come biomass next year.