Newsletter: Issue 38
Message from the Board
WATER LEVEL
The Carnelian Marine St. Croix Watershed (CMSCWD) signed a contract in late 2019 for a regular (at least bi-weekly) check and cleanup of choke points in the drainage channel south of County Road 4. A hydrology study is also in progress which should will be completed in 2020. It will hopefully recommend changes that can keep the watershed from flooding, but be prepared for a multimillion dollar cost.
The problem observed in fall 2019 in a tour with the CMSCWD of the area south of County Road 4 was drainage blockage. The new contract should solve this problem. However, the hydrology of the area has changed due to record rainfall of recent years and there is high likelihood of this becoming the norm.
All is not well with the water situation in MN, not just at BML. Last year, in a meeting in Washington County, a DNR Hydrologist described MN weather patterns, the changes to the earth’s atmosphere, and the future trends. In brief, the trend is higher temperatures and much more rain and winter moisture. There will not necessarily more snow, but wetter snow and winter rain. Average night time winter temperatures have increased dramatically. There has also been a large increase in night time summer temps, but only a 1/2 or 1 degree rise in daytime summer temps. The wetlands are full and will remain full since the aquifers are at very high levels. In effect, water is being pumped up into BML even during dry weather.
EURASIAN WATER MILFOIL
In 2019, PLM (our licensed herbicide applicator) treated 8.2 acres, and the BMLA treated about 1.5 acres. Unlike previous years when EWM was treated in mid-June, Procellacor treatment of 3.76 acres by PLM was delayed until July 16 this year. The cost per acre was about $2450. The BMLA spot treated the equivalent of approximately an additional .75 to 1.0 acres. The spot treating was lake-wide and mostly consisted of single plants or low density EWM in 10’ x 20’ spots. The largest spots the BMLA treated were only about .02 acres. Craig Johnson and Al Lepinski helped Mike Blehert do the spot treating. Jeff Dahlberg did the map/survey work.
Three of the 2020 PLM treatment spots were overlapping or next to areas treated in the last few years, and spot #1 on the June 25, 2020 lake map on page 2 was near a row of bullrushes that the BMLA has spot treated with mediocre success for several years. The green spots on the map plus six other spots including a few in the east bay and connecting channel were treated by the BMLA. There were many locations, some as large as .5 acres, that the BMLA spot treated the last two years where either no EWM or only a few plants were found and treated.
As of mid-July it was noted that EWM had a late growth start this year, and there was approximately 60% less than last year. There are several possible reasons why the EWM got off to such a slow start this spring and early summer. It could be related to weather, such as a warm March and then a cold spell that delayed the start of summer. PLM thinks the main reason is that the four areas treated in 2020 were near or overlapped with areas they or the BMLA treated last year. As noted in the 2019 final report, Diquat (a contact herbicide that quickly kills the green part of the plant but does not translocate into the root balls) was applied to kill the EWM rootlets to reduce spread and to weaken the plants so that the root balls might starve over the winter. Since there is always some herbicide drift, that could account for the slow 2020 start of growth in areas near 2019 treatment spots.
All four of the spots treated by PLM on July 16, 2020 were inspected on July 30th. Two spots were clear, no live EWM found, all decomposed/ broken into fragments too small to see or rake up. In the other two spots, the EWM was lying on the bottom, brown and some greenish brown. When raked most of it broke and fell off the rake. PLM said that this EWM would also die and decompose within four weeks.
A whole-lake search and spot treating was repeated in mid-August. Also, PLM treated three spots of EWM totaling 0.6 acres on Sept. 10 with a mixture of Diquat and DMA4. DMA4 is a systemic herbicide that translocates into the root balls, but it does not typically work well on small areas since it requires a 24 hour dwell time. The theory behind using a mix is that the DMA4 will move more quickly to the roots since the leaf structure will start decaying or dying soon after application. The BMLA applied this mix to a number of small spots on July 30 and August 18 and 24th. The results were quick. In less than one week all the EWM disappeared, meaning that the rootlets that otherwise would break loose and spread to new areas were eliminated. We will survey nine spots next year that were treated with this mix by the BMLA plus the three small areas PLM treated on Sept. 10 to determine the long term effectiveness.
Our five year project goal (2015 to 2019 five year period) was to reduce EWM to less than 10 acres. This goal was exceeded by over 50% and the BMLA is taking additional steps to hopefully continue to reduce the EWM to less that 2.5 acres in 2021/2022.
STARRY STONEWORT & ZEBRA MUSSELS
No Starry Stonewort or Zebra Mussels were found in BML in two searches by Blue Water Science (Steve McComas and staff) of the four major boat landings in BML: The County Park, Vets Camp, north landing, and the unimproved landing on the SE shore of the main lake. The first search was on Sept. 4 and the second on Sept. 22. For the Sept. 4 search a minimum of 50 rake samples was taken per access. On Sept. 22 searching was done by scuba.
FISH LIMITS
The DNR has hinted at reducing the limits in BML. One lakeshore property owner has expressed his opinion on this matter – impose a temporary catch and release rule. The size of bass, for one, has dramatically decreased gradually over the past few years. If you have an opinion on action needed regarding fish limits, please send your comments to richardburtonmn@gmail.com.
Membership
Membership donations should be sent to the BMLA – 12614 182nd St. N. Marine, MN 55047. We thank everyone who has already contributed for 2020.