Native Biomass FAQs

What is switchgrass?

Calvin Ernst with his arms around a tall bunch of switchgrass

Switchgrass is a perennial, warm season grass native to the majority of the U.S. east of the Rocky Mountains. It can grow from 4’-6’ tall and is adapted to a wide range of soils and climate conditions. Switchgrass generally needs relatively little herbicide, fertilizer, lime or water.


Where is switchgrass native?

Switchgrass is a tall-growing, perennial, warm season grass that is native to much of the U.S. Switchgrass was widespread in open areas before settlers populated an area, and remained in one place year after year.

What soil conditions does switchgrass need to do well?

Switchgrass is adapted to a wide range of soil types and conditions. Better soil may result in higher biomass yields, but switchgrass can make marginal lands productive.

When do I plant switchgrass?

There are a number of approaches to planting switchgrass. Depending on the situation, one may be more appropriate than another. For our production, we normally plant from mid-May through mid-July.

How is it planted?

Switchgrass can be planted in a variety of ways, including hand broadcast, machine broadcast, and no till. The condition of the ground being planted determines how much and what kind of work is needed prior to planting. Regardless of the tillage method used, the goal is to provide a seedbed that will allow good seed-to-soil contact, which is essential for the seed to germinate.

Also important in the establishment of a switchgrass stand is weed control, especially in the establishment year. This can be controlled through herbicide application, high mowing, or a combination of the two. It has been our experience that better weed control in the establishment year results in a more successful stand establishment. Even the most successful stands will take approximately three years to fully mature in Pennsylvania. Please refer to our guide, Native Warm Season Grasses and High Quality Biomass Production, for more information.

Ernst Conservation Seeds has dedicated substantial amounts of land, time, and effort to research the best herbicide protocol for warm season grass establishment. This work allows us to update our recommendations periodically to include any new information we have recognized.


Do I have to re-plant switchgrass every year?

No. Native, warm season grass is a long-lived perennial which, once established and with proper management, will produce biomass for a period of 15-20 years.

What is required to manage an established stand of switchgrass?

Switchgrass can be managed with a small amount of spraying in the first couple of years, then needs only traditional haying equipment to harvest it each year. As long as the biomass is being harvested, it is not necessary to burn the fields. For a more detailed description, please refer to our guide, Native Warm Season Grasses and High Quality Biomass Production.

What is required to harvest switchgrass?

Native, warm season grasses are harvested with traditional haying equipment readily found throughout the country.


How does switchgrass affect my soil?

Switchgrass has a root system that can grow up to 6’ deep. This root system can break through soil strata, such as plow pan or hardpan, and allows switchgrass to grow in the wide range of conditions that it does. This root penetration also improves the structure of the soil.

Is switchgrass invasive?

While switchgrass is a fierce competitor within the stand, it is not invasive in nature. This is due mainly to its fragile establishment phase. There are literally hundreds of other species capable of choking out switchgrass seedlings should they manage to germinate unintentionally. Native, warm season grasses are easily controlled by plowing or spraying with a herbicide, such as Roundup®.

What is switchgrass biomass used for?


There are many end uses for switchgrass biomass. Currently, warm season grasses are being used for mulch hay, bedding and grazing in some areas. This is in addition to the benefits of the standing plant. Research is ongoing to develop switchgrass biomass as a feedstock for cellulosic ethanol and other bio-chemicals and biodegradable plastics.

What has switchgrass been used for until now?

For years, switchgrass has been used for game cover, reclamation, and as a buffer zone along streams to keep harmful chemicals and sediments out of our waterways.

Why should I plant a crop that takes three years to reach maturity?

One of the most exciting characteristics of switchgrass is its potential to turn marginal land into productive land. Planting 70 acres of land that is not currently productive does not decrease productivity at all and will help position you as a biomass supplier as new markets and opportunities develop. At the very least, switchgrass will improve the soil quality of land that is now unproductive.

Do switchgrass roots cause problems with field tiles?

Ernst Conservation Seeds has been growing switchgrass and other warm season grasses for over 30 years. This might be possible; however, in our experience we have never seen this being a problem.

Is switchgrass a better energy crop than corn?

Saying switchgrass is a better energy crop than corn makes it sound like they are competing. This is not the case. If grown on the right ground and with proper management, corn can be a very profitable crop for a farmer, not to mention the fact that there is an existing industry that utilizes corn as a feedstock for alternative energy. There are arguments on both sides as to how efficient that industry is in terms of energy used to produce the alternative fuel, as well as about the magnitude and even the presence of environmental benefits achieved by the production of that alternative fuel.

Switchgrass can grow on marginal ground not ideal for corn to help turn the ground into a productive area. It requires less energy to plant, manage and harvest over a number of years compared to corn. This may give native grasses an advantage when comparing your energy investment to energy return. You must also take into account how the biomass crop is being used. The adoption of switchgrass as a feedstock for alternative fuels and/or sustainable fiber is just beginning in some areas, but gaining momentum in many others.

The important thing to remember is that there are pros and cons to both corn and switchgrass, as both have their place in providing renewable energy and/or sustainable fiber.

How much biomass does switchgrass yield?

In the Northeast U.S., it is not uncommon to see yields of 3-4 tons per acre with relatively little input.

What is biomass?

Biomass is “renewable organic materials, such as wood, agricultural crops or wastes, and municipal wastes, especially when used as a source of fuel or energy. Biomass can be burned directly or processed into biofuels, such as ethanol and methane.”

-The American Heritage® Science Dictionary. Houghton Mifflin Company. 19 Feb. 2007.

Can other plants be used to produce biomass?

All plants produce biomass of some sort. Wood is the most widely recognized and used to date. There are a number of other warm season grasses being evaluated for their biomass potential. These include big bluestem, little bluestem coastal panicgrass, indiangrass and cordgrass. Please refer to the list of Featured Biomass Species for more information.

What is renewable energy?

Renewable energy is “any naturally occurring, theoretically inexhaustible source of energy, as biomass, solar, wind, tidal, wave, and hydroelectric power not derived from fossil or nuclear fuel.”

-Dictionary.com Unabridged (v 1.1). Random House, Inc. 19 Feb. 2007.

Can switchgrass be pelletized?

Ernst Conservation Seeds and other groups have engaged in trial runs of pelletizing switchgrass biomass. While it has been proven that switchgrass biomass can be successfully pelletized, there are challenges. Switchgrass biomass, while very similar in some ways to wood fiber, does not flow exactly like sawdust. In some mills designed specifically to work with sawdust, the relatively low bulk density and unique physical properties of switchgrass can cause material handling issues. These issues are easily addressed with the correct engineering and mill design.


Do switchgrass pellets work in all wood pellet stoves?

Switchgrass pellets do not burn the same as premium wood pellets. They contain a higher ash percentage that acts differently than wood ash. Through research by a number of universities and pellet appliance manufacturers, there have been a number of stoves identified that are capable of handling switchgrass pellets. Please feel free to contact us. We would be happy to point you in the right direction.

Where can I buy switchgrass pellets?

Currently, we are not aware of any commercial production of pure switchgrass pellets being marketed for residential combustion purposes.

What is a switchgrass briquette?

Briquetting is an extrusion process similar to pelletizing that produces a larger product. In the process, switchgrass biomass is ground and extruded under tremendous heat and pressure. The end product has the appearance of a large pellet with a density that is approximately four times that of the original biomass. While these briquettes will not burn in pellet appliances, they could be a suitable fuel for larger combustion units that heat commercial or industrial facilities.


Where can I get switchgrass seed?

You can purchase switchgrass seed from Ernst Conservation Seeds, Inc., Meadville, PA. Click here to contact us.

What is Ernst Biomass doing?

Native grasses are some of the most efficient plants to collect and convert into cellulosic energy. The use of native grass as a renewable energy source is limited by our ability to harvest, transport and store biomass in sufficient quantity for use.

With more than 5,000 acres of native grass seed production, Ernst made the decision to develop a means of collection and densification of the crop residue for renewable energy or sustainable fiber.

Many methods of harvesting, collecting and densification were tried and rejected if they were not scalable or cost efficient. Today we use readily available haying equipment to harvest and transport biomass to our pellet facility.

Large, round or square bales are started through our pellet mill by putting through a tub grinder. Bales of different quality are mixed in a large feeder box with a walking floor. The rate of flow to the grinders, dryer and pellet mill is managed from a computer control room.

Biomass is burned to heat and dry our grass biomass before it goes through the final grinder and Kahl vertical die pellet mill. Pellets are cooled and stored for packaging.

We currently sell our pellets as an industrial absorbent and for livestock bedding.