Pollination at Sturm Berry Farm

This has been a slow spring for raspberry pollination. It's been raining nearly every day for several weeks, or so we've heard. John and I made our visit to Corbett last Sunday because it was the only day all of last week and this week that rain was not predicted. We hoped for some sun, and got perhaps a hazy hour or two, but most of the day was overcast. Temperatures were in the low to mid 60s during our visit.

The first photo is of black raspberry flowers. They are not very showy. Petals are small. This inflorescence had 6 flowers on it, more than most inflorescences. The flowers have many stamens wiht brown anther sacs in a circle around a cluster of white pistils in the center. I expect (though I didn't have time to observe) that most honey bees go after nectar from the side rather than from the top. That would limit their ability to move pollen from stamens to stigmas. Yet the flowers are getting pollinated. The flower in the middle is clearly developing a fruit.

This inflorescence gives a good indication of where we are in pollination. One flower with a developing fruit, one flower at the top right has lost it's petals and will probably show a developing fruit in a few days, two or three flowers are in full bloom with anthers in various stages of presenting pollen.

Here's a view of several rows of black raspberry in bloom. Can you tell it's in bloom? From this distance you can just make out small clusters of flowers in the closest bushes, if you know that they are flowers.





Despite the poor weather bumble bees and honey bees were busy foraging all day on Sunday. Rosie commented that the bumble bee population on their farm seems to have been increasing in the last couple of years. There are no honey bee hives on the Sturm farm this year, but honey bees have been coming in from elsewhere. My guess is that the bumble bees and honey bees are responsible for most of the pollination on the farm this year. I saw a few tiny halictids on the berry flowers as well, but they were mostly taking nectar from the side of the flowers, so probably not doing much pollination. The O. aglaia have not been very active as far as I can tell - more on that later.

Compare the black raspberry with marion berry flowers. The petals are much larger and showier, and the flowers can be seen from a distance away on the shrubs (photo below). The blackberries bloom a little later than the raspberries, but they are in full bloom now, and getting multiple visits from bumble bees and honey bees. There is even an ant crawling around on the lowest marion berry flower in this close-up.

Rosie put out a shelter with more of our Binderboard and O. aglaia next to the marion berries (scroll down to see photo). Something has been getting at the bees - maybe a humingbird? We covered the entrance to try to deter predators.

Our webcam set-up

Here are three views of the webcam in situ in the Sturm's raspberry field. As planned, the shelter, camera and solar panel that powers the battery for the camera are all sitting under a huge powerline tower. The bushes around the shelter are black raspberry.

The webcam resides in the white box between the bee shelter on the left (north) and the solar panel on the right (south). The white box provides protection to the camera from the elements. Mike built the box in his shop in Seaside, OR. Great job, Mike! You can see the black dome around the camera poking out underneath the box in the second photo. The camera can move 360 degrees to view all around the area. Most of the time we are interested in viewing the shelter, or the raspberry bushes nearby.

Don Sturm built the shelter. This one is quite cozy compared with the old apple crate that we were using last year. There is plenty of room for nests and bees, and lots of protection. We need to be careful that it isn't used by rodents, birds, or larger critters.

To help keep out unwanted vertebrates we purchased some screening from the local Home Depot and installed it over the opening to the shelter with pushpins and nails. Mice, spiders, wasps, and other small creatures can still get in, but at least hummingbirds and jays will be detered. Hopefully also racoons or possums, though they can probably chew through or pull off the screening if they want in. All the more reason for us to be able to monitor with the webcam!

If Rosie wants to get access to the nests or emergence boxes, she can take the mesh off of the nails holding it in place on the left.

Hummingbird Feeder??!!

We were playing with the webcam from the Sturm computer on Sunday morning, when all of a sudden, something blurry flew into the shelter. It took us a couple of seconds to realize that it was a hummingbird! OMG, I've never seen a hummingbird at a bee shelter before! Jays and woodpeckers are always a threat, and screening is recommended if bird predation is a problem. But hummingbirds?

We hadn't yet figured out that we can capture and save the webcam images, so I tried to photograph the computer screen to document this visit. See the blurry light blob just right of the left-most cottage cheese container - emergence box? That's the hummingbird. It was the best that I could do.

She didn't stay long. I think this little bird was a female because I didn't see any flashy metallic male colors, although the light may not have been right in the shelter. We watched her stick her long beak into a couple of entrances in the Binderboard, and then into the holes of the emergence boxes. We couldn't tell if she found any bees to snack on, but she certainly could have been eating them. It's also possible that she thought these were hummingbird feeders and she was looking for nectar.

We only saw the one visit, never saw her in person at the shelters. Before leaving the farm we covered the shelter with vinyl mesh to keep the birds out. Hopefully it will keep out our little hummingbird and her friends. Sorry hummers, these bees are not for you!

Webcam images at Sturms Berry Farm

Sunday, May 30 we spent the day at the Sturms' Berry farm to see how the bees and flowers are doing.

First, Rosie showed us what the webcam images look like on their computer. Here's John in their office, with an image of the raspberry bushes from the webcam. We could see the branches moving in the breeze. The images are great! I gather that the problem resides in the router. Mike has tried two different routers, one white and one black just to the right of the computer screen. Mike purchased the black router with the silver band around it. The internet provider, rconnects, sent the white route. But neither communicates with any computer except Don's. ARG!!! Any suggestions from our readers?
Here's a closer look at the computer monitor with the webcam image, this time showing into the bee shelter. A bit of the raspberries are visible to the right of the bee shelter. Below the image are easy tools to get the camera to pan and zoom in or out, right or left. A scroll bar on the right side of the image will move the camera up and down.
In this image we can see the status of the nests. No plugs yet. There was very little bee activity because it was overcast and chilly.

We can zoom in close enough to get a good view of the nest entrances. If any bees had been sitting there waiting for the sun, we would have seen them. The big yellow circle in the top left is a yellow push pin - Steve's idea - to give the bees something to orient to.

We were able to capture images from the webcam and e-mail them to me. It took a couple of days for them to show up in my in-box. The resolution is not great, but good enough for this blog.
Here's one of the images, another close up of bee nests in the shelter. Note that the top of the image has information about when and where the image was captured.

Next: Hummingbird feeder!

Bloom time, 2010

Sadly, we don't yet have a functional webcam for watching the bees. Mike says it's a problem with the internet server; Rosie is looking into changing servers.
Meanwhile, I'm on break from teaching biology at the College of Western Idaho, so we are taking a day to visit Corbett to see how the bees are doing. Rosie says it's been cold and rainy since the bees started to emerge. We hope they are still alive!
Jim Cane visited the Sturms a few weeks ago and set up a shelter with about 1,000 additional bees from his collection. I look forward to seeing them as well. He says there were lots of small carpenter bees, genus Ceratina, foraging on the weeds at that time (before raspberry bloom). I hope to see them today as well.
John and I drove up to Mosier, OR last night and spent the night at the Mosier House Bed and Breakfast. We recommend it if anyone reading this is planning a visit to the Columbia Gorge. Thanks to Cindy, our hostess, for a wonderful breakfast, and for keeping such a beautiful B & B.

Next... Bloom at the Sturms'.

Waiting for the Berry Season to Begin

The webcam is in place, as it the solar panel to power it. We are waiting for some technical details to be resolved before the webcam will be available on line. Soon, we hope.

Meanwhile, Rosie contacted me yesterday about the Osmia aglaia. They were out of town over the weekend. Before leaving she checked the containers of bee cocoons, and nothing had emerged yet. But the weekend weather was warm and apparently sometime over the weekend some of the O. aglaia started to emerge. She found them yesterday shortly after returning home. So, they have been moved to the refrigerator. There's no raspberry bloom yet on the farm. Blueberries should bloom soon. Meanwhile, a cold front came through and temperatures are back to the 40s and 50s, with some rain expected during the week.

Preparing Berry Bees for the Winter

Jerry, John, Glen and I visited Sturm Berry Farm on November 18 to see how the Osmia aglaia fared during the summer, to prepare the cocoons for winter storage and to clean the Binderboard® nests so they are ready to go out next spring.

Rosie removed the Binderboard® from the field in late September or October and stored them. When we arrived at the farm at 9:30am she met us with the Binderboard® in her truck, and escorted us to the garage of their house where we set up tables and equipment for the operation.

At first glance, the Binderboard® from the main shelter (under the power lines, see “Our Project Begins”, April 27) did not seem to have filled very well. Only about 25% of the tunnels were plugged at the surface. But when I put the board in the sun and looked down the tunnels, I realized that most had plugs recessed about a centimeter deep, and all of the boards from the main shelter were nearly full! Jerry was delighted. He has spent too much time cleaning Binderboard® that are only partially filled, and notes that it takes about as long to clean a partially filled board as a full one.

This photo shows two adjacent laminates that have been opened in Jerry’s cleaning machine. Some of the cocoons stuck to the top laminate, and some to the bottom laminate. In the fourth row from the left, all 9 cocoons stuck to the top laminate. Note that the mother bee left a small intercalary cell between the two innermost cocoons, and a small vestibular cell above the outermost cocoon. Intercalary cells have plugs on both end, but they are empty. Vestibular cells are also empty, except they are just behind the nest plug, the vestibule of the nest entrance, as it were.

The other nests between these two laminates had fewer cocoons, and intercalary cells were common. The middle tunnel, for example (7th from either side) has intercalary cells between each of the first 4 cocoons, then three adjacent cocoons, then a large vestibular cell just below the plug. I’m using the names that Karl Krombein gave to the parts of twig-nesting solitary bee and wasp nests in his ground-breaking book “Trap-nesting Wasps and Bees”.

Some of the cocoons contain adult O. aglaia, but some of the cocoons, more reddish in color, contained live prepupae, the final instar larvae. More on them in a future blog.

Rosie is getting a close look at Jerry’s cleaning machine in action. It mainly provides support for long Binderboard®, holding them in place during the cleaning process. Jerry is using a hand-held scraper to remove cocoons from all 13 tunnels per laminate in one motion. Actually, he is taking two swipes, one from the top to the center, and one from the bottom to the center. All the cocoons fall into the blue pan at the bottom. When the cocoons have been removed, Jerry moves the blue pan out of the way and replaces it with the grey pan. He uses a paint brush about the width of the laminate to brush bleach water on the laminates, and uses several scrub brushes to remove debris from the tunnels. The waste bleach water and debris fall into the grey pan. Then Jerry uses gripping teeth to open and lock into place the next two laminates. The gripping teeth are visible in the photo of the nests, above. In the view to the left you can see the cleaned laminates loop back around under the red shelf that holds the filled laminates.

The Binderboard® give us a good view of the nests, and Jerry’s platform speeds the process of cleaning the boards and preparing them for the next season. We were able to clean all of the boards at the Sturm farm in one 7 hour day with only one person scraping the nests. If bee populations continue to increase, this hand cleaning process could take more time than a grower wants to put into managing bees. Jerry hopes to add a motor to control the scraper and automate the cleaning process. That should cut down the time to process large numbers of bee cocoons and save the grower time and money.

Once the cocoons have been removed, it’s time to estimate our yield. Here’s Glen counting out cocoons in a ½ cup sample. We took 3 such samples. There isn’t much dimorphism between the sexes in size of the cocoons, unlike Osmia lignaria, so for this species we haven’t bothered calculating a sex ratio. However, we could by opening a small sample of cells to see what’s inside.

We found that there was an average of 310 cocoons per half cup, plus 17 cocoons with prepupae, about 5%.

Once the boards have been cleaned, we brought them into the heated mud room next to the garage to dry out.

At the end of the day we replaced the bolts and wing nuts, and tightened them as far as possible. The Sturms should tighten them more in a few days, and again in the spring when the bees are released.

And here is our final yield, divided among 8 cottage cheese containers, each holding a little over 1.5 cups of cocoons for a total of 13 cups. At 600 cocoons per cup, that’s an estimated 7,800 total cocoons. We released about 1500 O. aglaia cocoons raised on Sturm farm last spring, as well as about 1800 O. aglaia cocoons in straws that Dr. Jim Cane from the USDA Logan Labs gave us. The total release then was about 3,300 bees. We were able to more than double the population: a 2.3 fold increase. Perhaps we could have done better if there had been another Binderboard® to put out as the boards filled.

Dr. Cane sent O. aglaia cocoons to several other researchers and he reports an increase in all of our populations. That’s great news, and very promising for berry pollination.

Next year we’ll need more Binderboard® to support the increased population!
For now the cocoons are being stored on the porch of the Sturm home, where they will be exposed to outdoor temperatures. They are in a planter, covered with a wooden tray.