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We finished measuring plants in Jennifer’s Phenology plot at Hegg Lake WMA this Friday.
We measured many plants.
We measured about 2700 plants. Eight plants flowered this year. We visited another 1300 locations where we couldn’t find a plant (mostly because they had died). Here’s a map of the plot with the status of each location (click to see a bigger version)…
In addition to Echinacea angustifolia, we saw some good prairie plants in the plot, including lead plant (Amorpha canescens), yellow lady-slipper (Cypripedium calceolus), prairie rose (Rosa arkansana), Missouri goldenrod (Solidago missouriensis), silver leaf scurf pea (Psoralea argophylla), and many others.
It was a big job, but we were quite efficient. We laid out 50m tapes on every other row to help guide us. Four of us went out on Wednesday to flag positions 1 and 50 for all rows. That took ~2h. We started flagging positions 10, 20, but that was unnecessary. On Thursday we all went out and measured from 2-4 pm. On Friday we did two shifts: 10 -12 and 2:30 -5.
We were happy to be done.
On the way out we removed a weed that we had noticed the day before–spotted knapweed. We were careful not to touch it because it can be a skin irritant. I’d never seen this plant in the study area before.
Heading home.
What a great way to end the week. It was Katie and Laura’s last day. They are heading back to the Chicago Botanic Garden to prepare their posters and talks.
This afternoon we are going to measure plants in Jennifer’s Phenology plot at Hegg Lake WMA. Here is a script that makes a datasheet that assigns us rows to measure. The order is approximately 1 – 80, but they are slightly mixed up (just to keep us on our toes): measurePHENatHeggLakeRows.r
Thank you all for your hard work when we measured my Hegg Lake common garden a week back. It was by far the fastest the Hegg garden was ever measured and there were no rechecks besides can’t finds! Below is some information regarding the Hegg garden.
Total plants planted in May 2006: 3,945
Number alive in August 2006: 3,699 (94%)
Number alive in August 2007: 3,320 (84%)
Number alive in August 2008: 3,008 (76%)
Number alive in August 2009: 2,834 (72%)
As you can see the length of the longest leaf actually decreases from 2008 to 2009. However, there were way more plants with multiple rosettes this year than in years past. I think the leaf length decreased because last year there was so much duff on the ground that the petioles of the leaves grew really long. The plants definitely looked healthy this year after the spring burn than they did last year. What was really exciting was I had my first flowering plant this year in row 7 position 44! Below is a picture of that flowering plant, and one of everyone measuring at Hegg.
Also, thank you to everyone in the town hall for being so hospitable to my dad, Oscar, and me. We had a great week and except my weird heat rash (it eventually went away) it was a lot of fun. Best of luck with the final push at the end of the season!
Regards,
Jennifer, Oscar, and John
I thought I would spend some time comparing the 2006 and 2007 measuring of the plants at Hegg Lake. The Hegg Lake common garden is located on Minnesota DNR land and is approximately a 7.5 mile drive from the main common garden. In May 2006 3,941 seedlings were planted at Hegg Lake after they were first germinated and grown in a green house at the Chicago Botanic Garden. To learn more about this large seedling growth experiment read this description.
Measuring plants:
In both years we counted the number of leaves and measured the longest leaf. However, this year we also recorded insects and any herbivory damage on the plants. The average tallest leaf of the living plants was 6.4 cm in 2006 and 13.7 cm in 2007.
“Can’t finds��? and mortality estimates between years:
When we are measuring plants and can’t find a plant we don’t assume the plant is dead. Instead the measurer records that the plant is a “can’t find��? and places a flag in the position he/she was searching. Later we have a different person come back and searches for the plant so that two pairs of eye look for every “can’t find��? plant. In 2006 we had approximately 21% of the plants were found by the second person who went back and searched for the “can’t find��? plants. Our overall estimate for mortality in the plants first year of growth was around 6% with 243 plants that were “can’t finds��? after two people searched for the plant.
This year we have just started having the second person go back and search for “can’t find��? plants. We have a total of 698 plants that were not found by the originally measurer. This puts the mortality estimate at 17.7% plants (cumulative) however I feel this percentage will drop significant after the second person rechecks the “can’t finds��?.
One interesting note is there were 30 plants found by the originally measurer this year that were not found by EITHER person who searched for the plant in 2006. Therefore, in 2006 there were really (at most) 213 plants that died making the currently mortality estimate for 2006 at 5%.
Here’s a photo of the measurers and datatakers at the Hegg Lake common Garden on July 26th.
(L to R) Kneeling: Amy, Amy, Jennifer. Standing: Gretel, Ian, Andy, Ruth, Julie, Josh, Rachel, Colin, Jameson. Photo by Stuart–he measured too.
The weather for measuring turned out to be much nicer than predicted: Temp 85 degrees F; dewpoint: 70 degrees F; mostly cloudy with a W wind at 13 mph. It started raining, so we packed up to leave. As we were walking out the rain stopped, so we paused to take this photo. After the photo, it started to rain again.
We measured plants efficiently. Most plants have two leaves and the longest is 8-19 cm tall. It can be very difficult to find a plant because the thick grass is about 50 cm high. The only way to find it is to measure from another Echinacea plant. The ~4000 plants are spaced on 1m apart on a 80m x 50m grid. That can seem like a vast distance between plants. Jennifer made measuring sticks 2 meters long to help us stay on line and find the plants. After finding two plants you could keep on line fairly well and go fast. If there was a missing plant or a particularly sneaky plant, then it was very easy to get disoriented. Some folks worked in pairs (one measuring, one taking data); others solo. Here’s a photos of folks at work…
At last, after car trouble aborted my trip last week, I made it back out to Douglas County to join in field work with Team Echinacea. What a difference from the 2 days in late May, when Stuart, Jennifer, Andrea, Amy Mueller, and I were there searching for seedlings in the remnants! On Wed, the team numbered 12, and we made great headway measuring plants in the common garden. We were undaunted by the heat and humidity, though we did welcome every breeze. Today, we had the benefit of clouds all morning, and 13 of us measured quite a few plants at the Hegg Lake experimental site before rain, which we’d been seeing in the distance all morning, chased us in for lunch. The weather canceled field work for the afternoon, but we received instruction from Rachel about the upcoming work to evaluate species composition at her research sites, and I conferred with Stuart on analysis of pollinator visitation data before I headed back to the Twin Cities. I enjoyed the opportunity to meet the new members of the crew and working with them and look forward to the next time.
Hi all,
So I arrived up at the field site about a week and half ago to finish up monitoring flowering and help out with measuring and demo. Except for the recent death of my computer’s hard drive it has been an excellent start to my field season. As you may know flowering was about a week earlier this year with many more flowering heads than expected. I would have estimated around 800 (max) flowering heads but we had over 1,100 flowering in the common garden. Last year was also a huge flowering year (over 1,300 heads) because it was a burn year. I am excited to now have two years of flowering data on a large of plants in the common garden.
We have spent a large part of the last week I have been here measuring both in the common garden and at the hegg lake common garden. The hegg lake common garden was established back in May of 2006 to as part of my graduate research. It is about 6 miles from the main common garden on Minnesota DNR land. It has around 4,000 plants planted on a 1m X 1m grid. Today we had the entire field crew out at hegg lake measuring for a total of 13 people and measured nearly half of the entire plot just today…it was great!
Besides the field work I have been keeping myself busy in rural Minnesota by fishing (Ian has promised that I will actually know how to fish by the end of the summer), playing poker, and going to a dirt track race. In the near future I plan on flogging all non-Echinacea related activities that can be done in rural Minnesota….however now I’m tired so it will have to wait until the weekend.
Night!
Jennifer
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