Miscanthus – the magic plant
25 March 2019
In a Rural Delivery television programme last year Prof Steve Wratten of Lincoln University described Miscanthus as a “magic plant”. Although there was a degree of poetic licence in that statement, it is very understandable why he described Miscanthus in that way. But there are no magicians involved. Miscanthus is a truly remarkable plant that has so many advantages and options for commercial use that people who hear about it tend to think “This is too good to be true!”.
So they ignore it. The phenomenal success of Miscanthus therefore actually detracts from securing serious interest in both growing and using it. Contrary to people’s initial reaction, what seems like hype, is in fact true.
As an example without exhausting all possibilities, some of the advantages that Miscanthus can claim - supported by international as well as New Zealand experience - include:
Reputed to be the highest reliable annual per
hectare dry matter production plant for temperate
Having the ability to grow in low fertility soils and even waterlogged soils;
Providing sufficient shelter on pivot irrigated dairy farms to increase farm production;
Providing habitat for bumblebees and for indigenous skinks on dairy farms;
Giving farmers a crop that once established requires virtually no work but produces a significant and reliable annual income;
Insulating farmers against variations in primary product prices;
Being sterile and never spreading off-site;
Being easy to eradicate if no longer wanted;
Having a large number of markets including on-farm uses such as commercial mulch or calf bedding and green economy uses such as boiler fuel or renewable diesel production;
Being able to be harvested using conventional agricultural machinery.
Offering an option for waste disposal of high nitrogen effluent onto a crop that is so efficient at capturing the nitrogen that the leaching is less than what is achieved by indigenous or pine forest with just rainfall going on it.
Being very resistant to diseases and pests.
The Miscanthus that is being grown and used in New Zealand is a sterile, naturally occurring hybrid of two Miscanthus species whose ranges overlap in Japan. We have two clones in New Zealand - one that was obtained from the USA and one that was obtained from the UK - and both seem to be very suitable to New Zealand conditions.
Miscanthus New Zealand Limited (MNZ) is the company that imported the Miscanthus but prior to this, Miscanthus had to go through a rigorous vetting system that was carried out by the Environmental Risk Management Authority to ensure that such import would not pose any environmental risk to New Zealand. Their conclusion was that not only was Miscanthus not a risk, but it was so much in the interests of New Zealand to have it growing here that they waived the fee for their assessment.
Because of its sterility, Miscanthus does not produce seeds so MNZ has been multiplying it vegetatively. Using a combination of both tissue culture and specialist greenhouse techniques, the numbers of available plantlets have been substantially increased. In the past 18 months, MNZ has been producing Miscanthus rhizomes for commercial scale plantings and has been learning the pros and cons of various aspects of such planting.
The Miscanthus industry in New Zealand is now poised to take off as progressive landowners realise the enormous potential of this crop and begin to plant significant areas. One or two large end users have already started to plant their own stands and they have plans for doing more in the future.
Industries that produce high nitrogen effluent and that also have a demand for industrial heat are able to get the best of both worlds. They can spray irrigate their effluent onto purpose grown Miscanthus stands - with extremely low leaching of nitrogen - and then use the harvested crop to fire their boilers and create their industrial heat. They may also be able to benefit from the consequent reduction in net carbon dioxide emissions.
If electricity is required rather than heat, the Miscanthus can also be used for generation of the electricity. This has been being done for a number of years by a company in the USA.
This article is the first of a series that is being produced to educate people about Miscanthus so that New Zealand can get the multiple benefits that Miscanthus offers. Further follow-up articles will be written and published in the near future.