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September of SPOC

September has been consumed by trials that test the preference of Harpalus, as well as two species of crickets (Gryllus pensylvanicus and Allonemobius allardi). From August 20th until September 27th we ran 260 Harpalus trials which come out to 20 replications of the experiment (20 trials of each of the 13 plant species), 105 Allonemobius trials which come out to about 8 replications, and 72 Gryllus trials which come out to about 5 and a half replications.


You can see some of the physical differences between these two species of cricket in the pictures above. The first picture is of a Gryllus Pensylvanicus, the second is Allonemobius allardi. The third picture shows a Gryllus cricket molting. When I went to check that dish I actually thought this cricket was dead. Then it starting jumping, trying to shed its shell.

Gryllus pensylvanicus is one of the most common species of cricket over the majority of the U.S. and much of Canada. The Gryllus are the larger of the two species we have been testing. We’ve found them to be anywhere from a third of an inch to probably a full inch. It depends how old they are. They are known to be major predators of both seeds and other invertebrates. Similar to the beetles their population is known to max out in the fall because that it when seeds are most prevalent, after they have been shed (the crickets are commonly known as the ‘fall field cricket’). These bugs really differ from the beetles and the cricket species in terms of their life cycle because of their range in diet. It is generally accepted that years with greater seed abundance produce greater populations but the variety in available prey that the species has gives it really good flexibility. But, their ability to prey on invertebrates has been proven to give them an important advantage in years with worse seed abundance. It is actually debated how significant the effect of seed abundance is at all with these species because of this range. I found an interesting study talking about how certain genotypes in these types of insects can be preferable in years of greater seed abundance, and others can be preferable in years of worse seed abundance.

img_3221-1 It has been easy to notice from these Gryllus trials that they aren’t exactly picky when they are hungry. We have seen one bug eat all 26 seeds in one 24-hour interval. We have seen one bug eat all 26 seeds and a good amount of the paper towel that lines the dish. They are much more rambunctious than they other species we’ve looked at. The only two plant species that they noticeably stay away from are velvetleaf and hairy vetch because of their hard seed coats.

Final Growth

I spent weeks watering and tending to my forage plot in Hall, NY. With minimal rains, on the edge of a drought, the crops looked weak with no sign of growth. I left my plot in the best shape I could when I headed back to school, and on September 10th, I returned to see that the sparing rain had miraculously helped the cover crops prosper and the alfalfa to regenerate.

Cover crop and grass mixes

Cover crop and grass mixes

On September 9th and 10th, I was invited back to the Annual Seedway Kick-off meeting held in Geneva, NY. The evening of the 9th, we held a reception for all of the district sales managers and their dealers beneath them. A night of meeting new growers I never had to chance to connect with, and catching up with those I did spend time working with was a great experience. Both Seedway and CHR Hansen had tables set up displaying their new products for the upcoming year and enhancements made in their old products and literature.

Final alfalfa and clover stands

Final alfalfa and clover stands

The morning of the 10th, we had a plot day at the Hall, NY forage plot I maintained during my internship. We had three different stations, each spending an hour talking about the outlook for that crop in the upcoming year. The forages and cover crops were my showcase. Explaining the numerous hours spent and gallons of water used to try to make the plot look as well as it did for the conditions it faced. I was able to tag along with a group and listen to the pitches about the corn and the soybean plots as well. When he came to the CHR Hansen tent, I was able to pitch in and help my boss describe the products and when to use them.

Plot Day cover crop talk

Plot Day cover crop talk


Overall, the kick-off meeting was a good ending to my internship. Being able to see just how far my plot had come since the beginning and being able to connect with many growers and sellers, I was extremely grateful to have the opportunity to intern with such a welcoming company and community.


August of SPOC

erqh4r0hsrdlyl2l3lalkzdlmztl0z0h2rolqzvl7z1lizvlxzkhkzplrzozfl6l7r3zlzul3l6lqrjzlztzflfz2r3zWe’ve been collecting a lot more Harpalus pensylvanicus these past few weeks. We’ve been finding about 15-30 a day, which is a very sharp change from the beginning of August. Harpalus is a genus of ground beetle with different species commonly found throughout the contiguous United States and Canada. Harpalus pensylvanicus is known as a species prevalent in croplands. You can see they are pretty easily ID-able by their tan/orange legs along with a more shiny body in contrast to other similar looking species. As seeds make up the primary portion of their diet, they have been found to be most active in the fall after weeds and the like have shed their seeds. This is why we didn’t see too many throughout the summer. Different studies have worked at trying to pinpoint the species’ eating habits and preference. (As I said in the previous post, few if any of these studies refer to cover crops). They are an important predator of many weeds. One study told of how the trials they ran resulted in this species eating up to 90% of weed seeds. It’s important to consider that not all weeds are considered cover crops. There are weeds that are accepted as generally harmful to agricultural systems from both an economic and ecological perspective. The purpose of SPOC is to test the preference of these definitive weeds against other species of plants that can are often be thought of as weeds but can be used as cover crops, and to help re-contextualize the discussion surrounding seed predation to include cover crops.

One study (co-authored by Matt Ryan!) looked at Harpalus pensylvanicus preference of Giant Foxtail. Giant Foxtail is an example of a plant that isn’t considered useful as a cover crop, it is generally considered to be undesired in agricultural fields. The study was run through two seasons and found that not only did the beetles prefer newly shed foxtail seeds to older aged ones, but also the population density of beetles was found to hit its maximum at the same time foxtail seed shed began.

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The pictures above show the seed counter I spent time using in August to separate Giant Foxtail seeds from small debris and count them. I had never seen a machine like this before so it was fun to spend a few hours working with it. You set it so it rotates and vibrates with a certain amount of power depending on how heavy the seeds are you hope to count. The seeds travel around the cylinder while other debris stays behind. Eventually the seeds make their way to the top and pass across a laser as they are deposited out of the spout. They are counted one by one digitally.

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