high-pitched tunnels are a pop cock used to extend the growing season , specially for constituent veggie , flower , and fruit cultivator ( Pool and Stone , 2014 , 2015 ) . Their popularity is no surprisal throw increase yield and tone for many sort of produce , in addition to a price bounty for fresh , local products outside of the distinctive grow time of year . Construction disbursement for high tunnels can be prohibitory for some growers , but beginning in 2009 , the USDA - Natural Resources Conservation Service ( USDA - NRCS ) has funded a cost - share initiative for high-pitched - burrow construction through the Environmental Quality Incentive Program ( EQIP ) that has result in over 10,000 novel high tunnels since the start of the program ( USDA - NRCS , 2018 ) .
A grow number of farmers have begun to note sure output problems unique to high tunnels ; namely , an increase in some soilborne diseases , foliar diseases affiliate with greenhouse output , and an overall lessening in soil health ( Fig . 1 ) . The compounding of these proceeds can decrease industrial plant productiveness over time . The soil health topic in particular let in a going of constitutive matter ( which leads to degraded soil body structure ) and an increase in filth salt from irrigation under juiceless conditions ( eXtension Foundation , 2013 ; Magdoff and VanEs , 2009 ) . Another challenging aspect is the increase ontogeny rate of weeds due to increased heat in mellow tunnels ( Blomgren et al . , 2007 ) . Intensive cropping cycle also involve frequent fertiliser inputs , which for organic growers lie in of compost , manures , or other animal byproduct . These constitutive comment often provide phosphorus that exceeds plant nutritional needs ( eXtension Foundation , 2016 ) .
Many of these problems could be addressed by include covering harvest in high - tunnel crop gyration . Cover crops are known to increase organic matter , disrupt disease cycle , and , in the case of legume , lend nitrogen through symbiosis with rhizobia bacterium without increasing brininess or phosphorus to the same academic degree as manure , compost , or fertilizers ( Treadwell , 2009 ; Zieminski , 2018 ; Monfort et al . , 2007 ; Zhou and Everts , 2007 ) . Research search report crop in eminent - tunnel crop rotary motion is comparatively young , but initial findings are supporting . The primary challenge for farmers who want to grow underwrite crops in their high tunnels is how to balance the sentence require to grow a cash crop and a cover crop . In this article , we will discuss management bedrock , benefits and challenges , and seasonal options for include hatch crop in high-pitched - tunnel rotation in the northern United States , eviscerate on the flux farming and enquiry experience of the authors in the Northeast , Midwest , and Pacific Northwest .
physique 1 . High - burrow land showing poor grease quality with compaction and open cracking . picture acknowledgment : Elizabeth Perkus , University of Minnesota .
frame 2 . Walk - behind six - run-in verbatim seeder . Photo credit : Emily Swanson , University of Minnesota .
terminus is a more intensive task and can be unmanageable in a high tunnel , particularly with high biomass natural covering crops which may be very large by the termination date ( Fig . 3 ) . As with any cover song harvest , it is important to monitor each species and give the axe all the cover crops before the initiation of seed Seth . This will leave the greatest nitrogen contribution , as N will still be put in in vegetative tissue alternatively of sequestered in seeds . This will also keep cover crops from ego - seeding and becoming sess in the tunnel later . The most common method for book binding craw termination in high tunnels is pout , then tilling to incorporate biomass after a few daytime of drying the works material on the soil surface . The drying point after mow pretend the cover crops soft to till into the dirt . If field - musical scale mowing and tillage equipment is too orotund for the high-pitched burrow , it is important to feel a balance of machinery that will both fit into the tunnel and completely terminate the top craw . take the air - behind flail mowers and small riding mowers work well , but pocket-sized equipment , like a regular push lawn lawn mower , will only work on broken - biomass cover crops . Another option is to expend a weed whopper to end taller - develop cover crop , then use the cut biomass as a aerofoil mulch or chop up the material more finely with a push lawn mower prior to incorporation . Many get over crops necessitate tillage for thoroughgoing expiration , specially if they are mowed before flowering .
Figure 3 . overwinter cover crops in high burrow . Photo deferred payment : Elizabeth Perkus , University of Minnesota .
Once the cover crops have been in full incorporate , it is just to wait about 5–14 days to plant the play along cash crop . During this fourth dimension the fresh biomass in the soil will begin to fall in down , increasing soil moisture and the community of decomposers . In the first day of rotting , food may be less useable for craw . Also in this surroundings , newly planted seedling or germinating seeds can be dependent to rot or depredation ( Dufour et al . , 2013 ) .
Read more at eXtension ( Elizabeth Perkus , Anne Pfeiffer , Charlotte Thurston , Fucui Li , and Julie Grossman )
