Invasives & Arundo Control Project 2023-25
Contact us at Invasives@LakesideRiverPark.org to see if there's an Invasives/Arundo program available
What is Arundo Donax and why is it dangerous?
Arundo is an invasive plant species brought to this country by the Spaniards who used it for building materials. It looks like bamboo but is a member of the grass family. It grows in dense stands in any location where it can find water and is found choking many of the creeks that lead to the San Diego River in Lakeside
It is a fire hazard. The dense stands of dried arundo catch fire easily and 30-foot flames will engulf the stand. These stands allow fire to snake into urban neighborhoods that might otherwise not be subject to wildfire.
It is a flood hazard. These dense stands of arundo break off during high water events. They form thick mats that move down stream damming and diking up bridges, culverts and other in-stream structures, causing erosion, over topping and flooding.
It is not a benefit to wildlife. It chokes out our native willows and cattails and other riparian plants. Biologists have never identified a native bird species that uses it for either nesting or as a food source. It eliminates the songbirds that used to inhabit the creeks in Lakeside.
See also the California Invasive Plant Council report
Ok, how do I become a participant?
Please fill out and email the Right of Entry Agreement. We will use these letters as a part of the grant application process that allows the work to take place on your property.
If you sell the property, then the new owner will need to sign a Right of Entry Agreement in order to continue to be part of the project.
If you are a renter, then the property owner must sign the Right of Entry Agreement. The property owner will be responsible for communicating with the renters about the process.
Does everyone in a neighborhood have to participate?
No, but we try to get as many land owners in a neighborhood as possible to sign up. That way we can concentrate our machinery and manpower in one location, making the process more cost effective.
Neighbors can sign up later but the number of neighbors enrolled early will increase the priority in the program for the entire neighborhood.
How long does it take?
Generally one day of cutting and removal and three herbicide spraying visits. The heavy equipment will be on your site generally no more than one day. This is dependent on how many acres of arundo you have.
Removal can only take place between Sept 15 and Feb 15. Scheduling will take place well in advance during the summer.
Because arundo spreads underground, it will generally take about 3 years of treatment to completely control it. Then you will be committed to maintaining the property to keep it arundo free.
What about horses, chickens, dogs, and other pets?
The machinery is loud and the movement is random. It is best if horses could be removed or protected during the process.
For their own safety and comfort it would be best to kennel the dogs and other pets for the morning work is done on your property. As for the chickens, there will be a lot of commotion and the chickens will not want to be near the work area. The chemicals that kill plants in RoundUp will biodegrade into other, non-toxic compounds in about 12-24 hours when exposed to sunlight and fresh air.
What equipment and herbicide do you use? Will the herbicide hurt my other plants?
Most removal is done with a large hammer flail mower mounted on a tractor or bobcat. Hand crews with loppers or chainsaws will be used in areas that are too small for equipment and around fences and buildings.
The herbicides used are professional-strength versions of glysophate (aka Roundup). This herbicide only affects plants it is applied to and will not harm your water. The herbicide can only be applied when the wind is less than 5 mph (usually between 7 and 10 am) so it will not drift onto other plants. We add a harmless dye so we can see where we have sprayed. Our crews are expert at spraying just the arundo in areas where it is close to desireable plants.
Do I have a choice about the days the work crews will come?
Removal can only take place between Sept 15 and Feb 15. Scheduling of removal days will take place well in advance, during the summer. We will work hard to accommodate different scheduling needs.
How many workers will there be and what is their training? Will they store equipment on my land?
The number of people on the site at any given time would be site-specific and would depend upon the amount and configuration of the arundo on the site.
Equipment may be stored overnight but no more than one night without a specific arrangement with the property owner.
Paid and trained personnel will be doing the work. While we value our volunteers, they will not be used on this project.
If I let you on my property, does that mean that other people can use my property as well?
No, the Right of Entry agreement is very specific and allows only people who are working on the project to enter your land and only for purposes connected to the project. It does not create any public rights on your land. You can see the Right of Entry Agreement by clicking here.
What if something happens? Can I be held liable?
No, we carry full liability coverage, as detailed in the Right of Entry agreement. You do not need to provide any insurance.
Do I have a choice about which native plants you use for revegetation?
We will be glad to discuss the selection of plants with you but we will be working from a list of native plants that do well in a creek situation. Starting plant size varies from 1 gallon/D60 to rose pots (2” x 2”). This project won’t "landscape" your property but will restore it to a more natural setting.
I don’t want to wait until the project is funded. What can I do now about the arundo on my property?
1) Arundo removal is very difficult. All of the existing arundo must be removed (down to ground level, and the arundo must be chipped or otherwise disposed of.
If you decide to cut the arundo yourself, you can take it to Evergreen Nursery and they will chip it for free. Firesafe Councils also offer chipping. If you live in Eucalyptus Hills, El Monte Valley, or Wildcat Canyon, contact the firesafe councils in those areas to find out when the chipping days will be. If you area doesn’t have a firesafe council, consider starting one with your neighbors.
2) After the arundo has been cut, it will begin to sprout again. When it has reached 12-18 inches and has green leaves, it much be sprayed with professional-strength herbicide. Spraying needs to be repeated 2 or 3 times, as the arundo continues to sprout.
You can volunteer with Team Arundo at the River Park on Thursday mornings and learn how to safely apply herbicide.
3) Because arundo spreads underground, this process normally needs to be repeated every year for possibly several years.
The County has told me I can’t go into the riverbed to clear weeds. Will they let you do it?
When the County or other agency tells a property owner they cannot go into the creek bed to do this work on their own, what is left out of that statement is that they must have special permits to do it. You must have a 1600 Streambed Alteration Agreement from the California Department of Fish and Game and you must also obtain a US Army Corps of Engineers Regional General Permit No. 41: Removal of Invasive, Exotic Plants. These are complicated permits and not easy for the average property owner to acquire. In this case the San Diego River Conservancy did all of the environmental work needed to acquire these permits and now holds the permits for the entire San Diego River watershed. We are partnering with them (and with the Eucalyptus Hills FireSafe Council and the El Monte/Wildcat FireSafe Council) on this project. The actual permit and supporting documents can been seen viewed by clicking HERE.