This summer Jay Fordham conducted an experiment in
experimental plot 8 to determine an effective method for eradicating Fraxinus pennsylvanica, or green ash.
Team Echinacea is concerned with the spread of green ash in our experimental
plots because it crowds out native herbs. The Echinacea in exPt8 may be at
particular risk due to their young age relative to individuals in other plots.
A prior attempt to manage ash in exPt8 with triclopyr (brand name Garlon)
largely failed, resulting in only 3% mortality.
Jay devised three treatments of triclopyr application to green ash. The three treatments were 1) A foliar application where he painted all leaves with triclopyr; 2) A bark application where he cut each ash 10cm from the base and applied triclopyr to the remaining above-ground stem; and 3) A cambium application where he cut each ash 10cm from the base, scraped off the exterior bark with a knife, and applied triclopyr to the remaining above-ground stem. He divided exPt8 into 35 treatment sections and randomly assigned a treatment to each section. He then randomized the treatment application order and, with the help of the team, treated 438 green ash trees from July 22nd to August 8th. Jay then assessed ash mortality on August 27th and 28th and found the cambium application to be most effective. Jay presented his findings at the 2019 Midstates Undergraduate Research Symposium in St. Louis on November 1-2. His presentation is available to view and download here.
Triclopyr treatment
Mean Proportion Dead Stems
Foliar application
0.005
Cutting and bark application
0.333
Cutting and cambium application
0.498
In addition to the green ash management experiment in exPt8,
the team removed Bird’s-foot trefoil from exPt1 and along the bordering road.
The team also removed sweet clover from within and around exPt1, exPt2 and
exPt3. The team cut back sumac from the easternmost rows of exPt1.
Jay brandishing sweet clover plants that the team pulled in exPt1
In June the team planted Asclepias
viridiflora in exPt1 at regular intervals. Stuart initially assessed
approximately 124 surviving plugs prior to planting. Erin and Riley, while
pulling flags marking the planting locations in September, did not observe any
surviving milkweed plants. The team also planted Carex gravida and Carex
brevior in the path around exPt1. The team planted three of the same carex
species at each location in a triangular configuration. Erin shot the planting
positions with the GPS pole in the center of the three plants, or between two
where two survived, or north of a single plant where one survived. In October
she observed that approximately 2/3rds of the carex plantings were present.
Location: exPts 1, 2 and 8
Data/materials collected: Weeds were discarded outside the plot as they were removed.
Find information about Jay’s experiment at
~Dropbox\teamEchinacea2019\jayFordham
Find information about the planting locations of the
Asclepias viridiflora at ~Dropbox\CGData\Asclepias\plantPlugs2019.csv
Find the two GPS jobs containing the carex locations in
~Dropbox\geospatialDataBackup2019, saved in three formats in
temporaryDarwBackups2019, convertedXML2019 and convertedASVandCSV2019. The job
names are CAREX_P1_20190801_DARW and CAREX_P1_20191003_DARW.
Throughout the summer, I designed and collected
materials to establish an experiment in experimental plot 1 to study parasites
and their impact on the community of host plants they live in. Parasitic plants
are plants which absorb nutrients from neighboring plants. Parasitism is an important
part of nutrient cycling in many ecosystems and parasite scientists hypothesize
it to be an important part of prairie ecosystem maintenance.
This summer I collected seeds from five parasitic
plant species which are native to the prairie. I also collected the seeds of
over 100 species that can be commonly found in Douglas County, Minnesota and I
have begun experimental germination of them and will continue to do so in the
future. I developed a plan to plant Comandra and Pedicularis throughout exPt 1
and establish communities of 40 host species around them to address questions
about the impact native parasitic plants have on plant community members. In
late October I harvested biomass from the proposed parasite planting locations
to understand the species diversity and abundance present before planting.
Start year: 2019
Location: Douglas County, Minnesota; exPt 1
Overlaps with: Experimental plot management, Hesperostipa common garden
experiment
Materials collected: Parasitic plant seeds (Cuscuta
glomerata:18,000 across 6 individuals in 4 locations; Agalinis aspera: ~8,000
across 81 individuals in 3 locations; Agalinis tenuifolia: ~4,500 across
41 individuals in 1 location; Pedicularis canadensis: ~14,000 from 1
location; and Comandra umbellata: ~1,800 from 3 locations) and host
plant seeds (500+ seeds per host species, numbering approximately 100 species).
Seeds are stored at the Chicago Botanic Garden.
Additionally, 216 .1 x 1m strips of dried biomass are
stored at the Chicago Botanic Garden.
Data collected: Find data related to this project
including the proposed planting scheme in the cgdata repository in
~cgdata\summer2019\Hemiparasites
Last Friday, I was dispatched by Stuart to find the number of plants/ achenes planted in each experimental plot, along with the number alive as of a recent year (2017-2019, based on the plot). Although records of some plots were a bit harder to come across that others, I was able to compile data from each plot (besides p10 – planted 2019 – data coming soon). This would not have been possible without the help of Gretel, so thanks GK! I have attached a small datasheet with the survival data.
In the history of the Echinacea Project, the team has sown 31,888 Echinacea viable achenes in experimental plots. There were many more sown that likely did not have a seed. Team members found 3634 seedlings from these seeds, not including Amy D’s experimental plot 3 and remnant seedling refinds. The team has planted 18,869 Echinacea seedlings in experimental plots, not including p10 – planted at West Central Area HS in 2019. Finally, 7090 Echinacea are currently alive in the experimental plots!
It’s raining. We searched for sweet clover south of p1 (experimental plot 1) and pulled about 70 stems. We started walking through p1 and encountered three clumps of bird’s-foot trefoil in rows 31 & 32 near position 878. As we were extracting the three bad plants with garden knives, the skies unleashed a downpour. We hastily gathered the leguminous carnage and headed back to the Hjelm house.
In 2014, members of Team Echinacea did an experiment to test methods of removing Hawkweed. Last year Ali assessed the results of the different methods that they used: cutting the head and painting the stem with herbicide, painting the leaves with herbicide, hand pulling with and without tools, and a control treatment. You can read her post describing the experiment and with the results from 2015 update here and the original post with methods here.
I went back to the treatment plots this morning and assessed Hawkweed percent cover two years after the treatment. The plots with the lowest percent cover this year were those where they removed hawkweed by hand, with tools. These plots also had the smallest percent change from 2015 to 2016, indicating lasting effects of removal. This was in contrast to those that had been treated by painting leaves with herbicide, where plots had an average of 4x increase in Hawkweed. From now on, we’ll use this method to remove Hawkweed in P1. We’ll assess percent cover in the treatment plots and the status of other Hawkweed plants in p1 to keep track of our progress at eradicating Hawkweed from the common garden.
The gang had a busy day today, almost all of it in the warm June sun. Alyson continued setting up her experimental plots in the Staffanson bog, and spent the afternoon measuring canopy cover and soil pH for her IS project. Meanwhile, the rest of the team (minus Gretel, who was setting up work for q2 juvenile counts) picked up our fleg begs and counted Hesperostipa spartea and weeded in p1. Amy and James found one H. spartea specimen with 137 seeds! We are now up to 17 out of 59 rows surveyed. Meanwhile, Will, Alex and Per led the crew in weeding out the non-native yellow sweet clover (Melilotus) from the periphery of the plot area. Hopefully we eliminated a lot of potential seeds form the seed bank, meaning that in future years the rows will be devoid of this weedy legume and the study Echinacea will have less competition. Stuart also showed me what poison ivy looks like for the third time, and I still don’t think I could pick it out of a lineup.
Per with a bundle of sweet clover picked from around p1. This is probably less than 10% of what was removed today.
After some brief (or for Alex, who was cleaning the bathroom, not so brief) chores at the Hjelm House, the team returned to exPt8 (experimental plot 8) to search for juvenile Echinacea crossesplanted in 2013. This meant more time bent over, although now instead of looking for seedlings we were looking for melted bits of toothpick (which were placed to mark seedlings). Some seedlings were in great shape — Alex and I found a couple with basal leaves over 10 cm tall. Others were not in great shape, either dead or missing like Jimmy Hoffa. We got about a third of the work for qGen2 this afternoon. It may rain tomorrow, so we’re bracing for indoors-work and hiding our bicycles inside.
Using a pink sword to claim the new seedling (left) for Team Echinacea. We used cocktail swords to denote seedlings germinating this year from achenes sown in 2013.
Today we started in P8 by pulling some sweet clover. It was not a task to be taken lightly, only the heartiest could master the “full pull.” It was really in the ground and being held tight by Brome grass. We did manage to pull on and get a lot pulled out and removed. Hopefully there will be a lot less in the plot from now on. Below is a picture of our bundles. We figured they were at least as big or bigger than Gina! We broke for lunch and then started flagging in P1 and at Hegg lake. We were all getting quite good at finding plants and/or staples and almost had all the 5 meter flagging done when a sudden, unexpected rain shower left us running for cover!
Dwight and Stuart broadcast native prairie seed in experimental plots p1 & p8 on Friday. At 34 °F (1°C) it was the warmest day in a month. It was also very windy –great for spreading seed! We broadcast Bouteloua curtipedula, Schizachyrium scoparium, Galium boreale, and Phlox pilosa directly on the snow. There wasn’t much snow and it was melting. We broadcast Lathyrus venosus in p1. We stored about half of each species, except L. venosus, in the Hjelm house to broadcast in the spring. (Hedging our bets.)
These are the methods for the hawkweed removal experiment performed by Allison Grecco, Cam Shorb, Jared Beck and Elizabeth Mays in experimental plot 1. The percent basal cover of hawkweed in each quadrant is to be determined by Team Echinacea in Summer 2015.
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