Lesser Celandine

Photographs and Notes

Part III NOTES

Methods of removing celandine

Shoveling works when removing isolated clumps that are too numerous to be hand-pulled. But shoveling can disrupt native plants too. In 2001, it took eight hours to overturn celandine and separate it from soil over about seven square yards.

Plastic sheeting as a cover was tried in 2002. After about six weeks pale leaves of celandine seemed moderately healthy in the moist ground under the plastic. Green leaves thrived at the edge.

Spraying is the only practical method to remove well-established celandine. The Park has been using Rodeo, which contains glyphosate, considered one of the least harmful chemicals. Glyphosate works by preventing the synthesis of three amino acids which most plants (but not animals) need.
Read a useful website on glyphosate.
Read a major paper on research in Rock Creek Park.

Harrowing A British website on organic weed management says, "Meadows should be well harrowed in spring to drag out the roots and tubers. If lesser celandine is very abundant it may be better to plough up a meadow and put it down to root crops for 1-2 years before sowing down the grass again." Harrowing would destroy native plants, but they would die in any case among dense celandine.

More effective celandine removal - thoughts in early 2008

Isolated clumps of celandine have been arising in the woods despite spray efforts. Do viable seeds develop in the clumps that are sprayed, but do not turn yellow? Do viable seeds form even in clumps that eventually die? If so, preventing massive spread may be very difficult.

Celandine from nearby yards can be expected to re-enter the Park. Friends of Sligo Creek should make a point of informing homeowners about Park removal efforts. We could also offer to provide a sprayer, paid by our funds, and request an owner contribution to help defray the cost.

Author's history of celandine in Sligo

2000 I learned the name of the plant and noted that it was spreading.

2001, probably I asked Park Maintenance Manager Pete Boettinger to observe the celandine and remove it. Pete was sympathetic but did not have the resources.

2002 Again, Park resources were not available.

2003 Again, Park resources were not available.

2004 In about February I researched grant funding. The Summit Foundation stretched its policy of funding only programs which could bring about a permanent difference, and gave Friends of Sligo Creek $4,000 for the Park to contract out for sprayers. Rob Gibbs from the Park had two sprayers from the company EQR apply Rodeo. Backpack sprayers covered the area from Kemp Mill to New Hampshire Avenue.

2005 The Park did backpack spraying. When time ran short in early May we contracted for outside help, using funds ($240) from a larger grant provided by the Chesapeake Bay Trust. The above areas were again covered, and also woods behind Takoma Middle School on Piney Branch Road.

2006 The Park contracted out for backpack spraying with Montgomery Weed Control, Inc., using funds from the 2005 source. Paul Carlson from the Park also did backpack spraying in Sligo. It was probably in this year that Paul sprayed at Long Brnach (near the Recreation Center-to-Library footbridge) for the first time.

2007 Paul Carlson again did backpack spraying. It was noted, especially in upper section 7 woods below Dennis, that despite spraying many new clumps of celandine were forming, raising the question of whether success is possible. Spraying had to be cut short for lack of sufficient sprayer time and because too many rain days forced delays in the spray schedule.

Locations of Lesser Celandine
In 2004 Sligo Creek Park had four large areas of celandine between the headwaters and Riggs Road.

1. Kemp Mill area, along the dirt trail between Channing and Colt Terrace Field. 2007 - May hardly exist now; we need to look in 2008. Similarly between the holding ponds on Dennis Avenue and townhouses to the west, in about 2006 the Park sprayed sevral large areas. Celandine was not seen in 2007. The ponds were dredged in about this year, but the celandine area is not know to have been included in the work area.

2. At Flora Lane Tributary just inside the Beltway, on both sides of the walk path and down nearly to the Creek. 2007 - Celandine has spread some. The area has not been completely sprayed more than once.

3. In the old baseball field between Colesville Road and the Brunett foot bridge (upper section sprayed in places most years, but never the lower). 2007 - Celandine has edged closer to the Brunett foot bridge in spots.

4. In Prince Georges County, much of the area above East-West highway (not sprayed to my knowledge). In 2006 we reported a small patch at the top of the hill with path leading to the park, near 15th Street. Prince Georges County Park Manager Kyle Lowe had it sprayed, by John Dillon. Celandine existed in 2006 in small clumps on the floodplain between New Hampshire and the County line.

Between Dennis and University, no celandine was known in 2004. Since then occasional clumps have been found near the creek and destroyed. In 2007 an alarming medium-size, untreated patch was discovered behind town houses on Lester, north of Windham Lane. This is the topmost edge of what seems to be Park property. Celandine is also on adjacent building property, and steps being taken for removal.

Smaller areas of celandine also existed in 2004:

• Near the large vernal pool in the restored section of Wheaton Branch, downstream from Woodman Avenue. This spread and was sprayed in 2006, but probably not in 2007.
• At the sand bend of Sligo in the midsection of the soccer field opposite the golf course. This may be gone, but there were many new clumps in the general area by 2007.
• On the floodplain between Flower Avenue and New Hampshire. This was sprayed probably each year until 2007, when there was no time to address that part of the Park.

The name and medicinal uses of lesser celandine

A 19th century British writer, John Clare, wrote that celandine is "used in herbal medicine for the treatment of piles, or haemorrhoids, eithr as an infusion or with the whole plant being macerated in boiling lard." The sap was used to treat warts. (The Natural History of Prose Writings of John Clare, ed. by Margaret Grainger; Clarendon Press, Oxford, 1983).

Submitted by Sally Gagné
February 2008