Invasive Plant Control at Crosby Sanctuary

Chinese tallow treeIn late July a small crew worked at Crosby Sanctuary to remove invasive plants that had grown up over the past few years. We haven’t done much work on invasive plants in a while, so they have come back more than expected. The main offenders were camphor tree and Chinese tallow tree, but there was plenty of Japanese climbing fern and air potato to go around. We also controlled some Mexican petunia and Johnsongrass along the ditch. Wild taro is also very abundant in the ditch and downstream wetland, but we didn’t have the time or energy to deal with them that day. Do any of these invasive plants sound familiar? They are all very common in our natural and urban/suburban areas of northeast Florida.

The Ixia Chapter of the Florida Native Plant Society initiated the workday, so props to them for helping motivate us to deal with our invasive plants. A special thanks to Ixia Vice President Adam Arendell for coming out to help!

Air potato beetles CBW 20150926 082112How were these highly invasive plants removed, you might ask? Well, if you read the guidance from IFAS or other sources, then you will hear the term Integrated Pest Management approach. This involves careful planning and implementation of multiple methods over time to manage invasive plants. The methods include prevention, biocontrol, mechanical removal, chemical control and anthropomorphic manipulation by fire, flood, drawdown, etc. The two methods currently being implemented at Crosby include biocontrol and chemical control, as well as maybe a bit of prevention. Air potato beetles were a biocontrol introduced in Clay and Duval counties about ten years ago and their larvae have been seen at Crosby feeding on air potato leaves. They are partially effective at keeping the air potato in check, but not completely wiping it out. The larvae need something to eat and air potato is all they eat.

Chinese tallow tree girdledThe other control method was chemical control by careful application of herbicides to the target invasive plants only. Two herbicides were applied using frill and girdle, cut stump and foliar applications (spraying leaves). Garlon 3a herbicide was applied to woody trees such as camphor and tallow in a girdle cut at the base of the tree (larger trees) and to cut stumps (smaller trees). Rodeo herbicide was applied by foliar application to herbaceous species such as Japanese climbing fern, air potato, and Johnsongrass. Some may question the use of herbicides, but they are absolutely necessary in the fight against invasive species. That said, common sense tells you not to overdo it with the herbicide. When used sparingly and targeted to the invasive plants only, then herbicides can be used effectively and safely within natural areas and preserves. It’s when they are applied in excess or over too large an area at one time, such as farms or aquatic weed infestation areas, that they can become a real problem.

~ Pete Johnson, Crosby Sanctuary Director

  • Urgent Request to Members and Supporters

    by Pete Johnson, Acting President

    VolunteerDuval Audubon is the only conservation organization that has been established in Duval County since 1939. Yes, that’s 85 years this year! The chapter has changed a lot over the years, but the core mission has stayed the same, to celebrate and conserve our amazing bird diversity in Northeast Florida. Our official mission is “Connecting People with Nature, conserving and restoring natural ecosystems, focusing on birds and other wildlife.” We continue to do this for our membership and the community, but we need your help.

    As many of you know by now, previous chapter president Carol Bailey-White stepped down last year after 3 years as president and 10 years of serving on the board in various other capacities. She is still dedicated to our chapter and continues to volunteer with our website and social media outlets. We were excited when new president Rich Egan came on board for the 2023-2024 year. However, he resigned after a few months for personal reasons and was not able to continue leading our organization.

    That’s where I stepped in as Acting President through the remainder of the 2023-2024 term. As Vice President and long-time director of Crosby Sanctuary, it was my responsibility to take on this role. However, my career obligations are very demanding, and I have a limited capacity to continue in this position. We need someone with the time and energy to devote to our chapter to step up and submit an application to be President. We have a great group of Board Members to support you. It’s a manageable role that anyone can reasonably do.

    Preferably, we are looking for someone who is retired or works part-time and has a little more time to devote than someone working full time. However, we are not limiting the field if the right candidate wishes to step up. I’ll even volunteer to stay on as Vice President for the first year to provide support.

    We have position descriptions available for review. Please, if you have any interest just contact us at This email address is being protected from spambots. You need JavaScript enabled to view it. and request a position description for review.

    You can This email address is being protected from spambots. You need JavaScript enabled to view it. and/or apply using our online application form (a paper form is also available if you prefer). Thank you!

     

  • Having Your Voice Heard

    Beginning Bird Walk at Ft Caroline 20221106 by Piyush NeekhraYour membership in Duval Audubon strengthens our messages to the public and government leaders. The more members we have, the more effective our voices for birds and bird habitat will be. Education about conservation issues is an important part of our work. Help us amplify our messages. Your membership means a better community for people and birds and other wildlife. Join today and help make Duval, Clay and Nassau better places for all creatures to live.

    Unsure of your membership status? Reach out to our membership director Christine Lucas at This email address is being protected from spambots. You need JavaScript enabled to view it..

     

  • Upcoming Activities

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    We look forward to seeing you soon!