Rodale hosts the Pennsylvania Women in Agriculture Network

The PA Women in Ag Network (PA WaGn) and the Rodale Institute partnered on June 4th to showcase Rodale’s latest research in organics and provide a great opportunity for farmer-to- farmer networking. Are you interested in measuring your soil organic matter instantly in the field? Are you tired of throwing away plastic mulch? Read on.

Ann Stone from PA WaGn and Jeff Moyer from Rodale kicked off the day, welcoming us to Rodale. Then we were off to a tour of the farm led by researchers Jeff Moyer, Rita Seidel, Alison Grantham and their team. After a fabulous lunch, we spoke with Temra Costa, author of “Farmer Jane,” and learned about certification from Pennsylvania Certified Organic, and opportunities available for farmers from Natural Resources and Conservation Service. Here are a few highlights.

Alternatives to Black Plastic – Many of us use black plastic mulch. The alternative in a weedy field can be days lost to cultivation and hoeing. And boy do those tomatoes and melons grow faster and produce earlier with their roots warmed under plastic. But in the fall when it is time to rip up the plastic, you like me, might not be as cheerful. Plastic is expensive and time consuming to rip up, and the bill at the landfill is expensive. “Not only do none of us want to see our precious resources buried in the landfill, research shows that we lose 30-40% of our agricultural chemicals to runoff in fields with black plastic compared to un-mulched fields,” says researcher Alison Grantham.

Rodale researchers are hoping that rolled cover crop mulches can provide a viable alternative to plastic mulch. Grantham and her team planted vetch, rye and vetch/rye cover crops last fall. In early June they rolled or flail mowed all three types of cover crops. Tomatoes will be planted directly into the rolled or mowed cover crop by hand. The cover crop will act as a mulch, suppressing weeds and keeping the ground moist. They will compare the yield, and quality of the fruit to other plots where the tomatoes are planted into regular black plastic. Think of it this way. Instead of tilling up the ground in spring, and going to all the trouble of hauling in tons of straw to mulch your tomatoes or other crops, you could grow your mulch in the field. There is little question that growing your own mulch can work. In fact, I visited a farmer yesterday who does just that. But the question remains whether the yield you may lose to colder soils is made up with fewer costs and less labor.

Can I track my soil carbon? First, why would you want to track soil carbon? You might have heard of carbon sequestration. We know that carbon in the atmosphere is contributing to global warming. Sequestration is a way to store carbon – in the soil, in trees, in the ocean, where it can’t cause problems in the atmosphere. As we acknowledge that it is important to keep carbon out of the atmosphere, there is increasing talk of paying farmers “credits” for practices that keep carbon in the soil (organic matter is primarily carbon). So far farmers would be paid for doing a number of practices scientists have found are good at storing soil carbon. But we know that every farm is different, and the science showing which practices work is far from complete. If we can easily track how carbon changes on each of your farms, and see where and after which practices it changes, it will give us much better information about what practices really store carbon in the soil. Instead of paying for what we think works, we would be paying for what really works. Since farmers are great innovators and know their farms the best, tracking soil carbon in real time, with easy measures could be immensely effective.

At Rodale, researcher Elaine Viglione (right) is working to develop a mobile lab that would measure soil carbon right there, in the field. The lab is simple – a cardboard box holds a plastic tube that you lay a core of soil in. Elaine runs a hand-held tool called a spectrometer to measure the visable, near-infared and mid-infared reflectance (color) of the soil core. Remember the colors we see are the distribution and wave length of light reflected off a surface interpreted by the light receptors in our eyes. This machine is acting like a more sensitive version of our eyes “reading” the light reflected off the soil in a core from your field. Elaine will be comparing the readings from this machine to the numbers from traditional soil carbon analysis to see if the tool can give us better and quicker data.

Keep an eye out. It may not be too many years before you are able to measure your contribution to slowing global warming with this quick, effective technology.

What do women have to do with how America eats? The new book “Farmer Jane,” profiles women farmers, educators, advocates and chefs who are changing the way we eat. We were lucky enough to speak with Temra Costa, the book’s author. A few years ago Temra looked around the table in the non-profit/advocacy end of sustainable food systems and realized, “Hmm, we are mostly women.” Not all the movers and shakers in the sustainable food and farming movement are women, but many are. When Temra looked closer, she realized that of the top 15 national nonprofits focusing on sustainable agriculture issues, women comprise 62 percent of the employees and 60 percent of the executive directors. As mothers of children, nurturers of health and the ones in control of 85 percent of household budgets, women have the largest impact and concern when it comes to what they feed themselves and their families. Just look at your CSA members – most are women. On the farm, women are one of the fastest-growing demographics to own and operate farms in the United States and they are tending toward diversified, direct-marketed foods that create relationships with eaters.

Temra highlights many women in the sustainable food and farming movement in her book. Of course, there are many more (and men as well as women), Temra admits, but she hopes the few she was able to describe will be an inspiration.

Spinach Leaf Miner

Spinach leafminer seems to be more prominent than usual this spring in Southeastern Pennsylvania. After receiving a call, I started asking growers and many of them have seen it in fields that are not usually affected. I have seen leafminer damage in Swiss chard, beets and even arugula, in addition to spinach this year.

From a distance, damaged leaves will appear to have blisters – white squiggles on the leaves. When you take a closer look, you may be able to see the legless, yellowish-white larva burrowing between the leaf layers. When the larva is mature, it will cut a hole in the leaf, drop to the ground and pupate. Two to four weeks later it will emerge as an adult fly. The flies are small – 1/4-inch long. Apparently, they are gray with black bristles, but without a hand lens they look like any other small fly to me – perhaps a little slimmer. The adult flies lay clusters of small, white eggs on the leaves.

Usually early spring plantings escape damage. This year the soil temperatures warmed up sooner in places – possibly contributing to earlier than normal problems.

What can you do? Start with cultural controls. Once the leafminer larvae are inside the leaf they are relatively protected from pesticide applications. Crop rotation is important for leafminers. Spinach, beets and Swiss chard (and apparently arugula) are hosts. Make sure you plant in an area that has not seen these crops for two to three years. The spinach leafminer flies overwinter in or near spinach fields and emerge in April and May to lay eggs. Planting early or overwintering spinach can help you escape significant damage, especially if you will be harvesting before mid-May. Deep spring plowing can also reduce the numbers of overwintering fly pupae.

In smaller plantings, they recommend using row cover. The row cover keeps out the egg-laying adults. Install the row cover immediately when you plant, and keep it in place until harvest. One note of caution: If you place row cover over beds that have overwintering leafminers or flies enter under the row cover, you are trapping them inside. The naturally-occurring predators and parasitoids would normally be helping you keep the populations down. Instead, you have created a haven for leafminers and they will multiply!

Unfortunately, if you have significant leafminer problems now, it is hard to go back and do cultural controls. If possible, it is a good idea to pick and destroy leaves with leafmining damage before the larvae emerge and lay eggs for the next generation. On a small scale it is possible to scout for and destroy eggs. For organic growers, Entrust is the only labeled product that has shown any efficacy in research trials. It will penetrate leaves and so it has more activity. Other products, including garlic, may be effective; unfortunately research trials are lacking to back them up. I have also heard of growers using beneficial nematodes. Non-organic growers can use abamectin, cyromazine, dinotefuran, permethrin and
spinosad products.

See the 2010 Production Guide for Organic Spinach at www.nyipm.cornell.edu/organic_guide and Commercial Vegetable Production Recommendations at http://horticulture.psu.edu/node/465 for details.