We have received a NE-SARE Farmer grant for this project and will be building and trialing the sprayer in 2014 and 2015. Andrew Landers from Cornell will provide technical assistance to the project.
The goal is to develop a modular sprayer which will have attachments suitable for spraying trellised, staked and low to the ground crops in a high tunnel. We have used both Solo backpack and caddy style sprayers with hand wands/guns and found them to be both slow and inaccurate. The sprayer we will build should take less time to get through the tunnel than our existing sprayer and do a better job of applying materials uniformly and at the label rate.
I'm interested in learning what other growers, especially organic growers, are using to spray in their tunnels, the materials they are trying to apply and the concerns they have with their current sprayer and spraying method. The materials we have used in our tunnels include Kaligreen, pyganic 1.4, entrust and neem products.
You may be aware of an excellent existing SARE study on modifying backpack sprayers to make them more user friendly and better at applying a consistent rate of product:
http://snyderfarm.rutgers.edu/snyder-backpack-sprayers.html
Based on recommendations from this study, we recently purchased a Jacto backpack sprayer. It hasn't been delivered yet, so I can't comment about how well we like it. It does have a large piston pump compared to a Solo (less fatigue), the ability to put two flexible spray nozzles on a single wand, and various pressure regulators to put out a consistent flow. Like you, we're interested in minimizing the amount of time we spend going through the tunnel or field with a backpack sprayer.
Thanks for mentioning this study. I reviewed the project report and outreach materials while preparing my grant application. The issue I have with the backpack sprayers is that they are primarily spot sprayers and it isn't really possible to use them in a way which results in uniform application rates. Plus, it is slow going, even with two nozzles on a wand if you are spraying a trellised crop like tomatoes which may be 8+ ft. tall.
Based on our farm experience with both Solo backpack and caddy style sprayers, we have determined that for us it will make sense to build a boom type sprayer that we can pull through the tunnel.
I have extensive experience modifying pump and CO2 backpack sprayers for applying treatments to research plots which could easily be applied to small-scale crop-production or mixed planting conditions (GH, trellis, field). I mainly dealt with R&D Sprayer (Bellspray Inc). You could check out their site for ideas if you're not already familiar with them.
Thanks for posting the link. I wasn't aware of Bellspray's products.