[MAIPC] groundcover suggestions

Thu Mar 22 03:14:42 PDT 2018

Regarding “Although the straight species of Panicum virgatum (switchgrass) is native, it is a strong competitor and not suitable as a temporary fill-in to prevent weeds” USDA ARS reported their study that it is invasive as a mono-culture but not invasive at all if planted with enough other native species. 

Marc Imlay, PhD

Conservation biologist, Park Ranger Office, Non-native Invasive Plant Control coordinator. 
(301) 442-5657 cell  ialm at erols.com <mailto:ialm at erols.com> 
Natural and Historical Resources Division
The  Maryland-National   Capital   Park  and Planning Commission
www.pgparks.com <http://www.pgparks.com/> 

From: MAIPC [mailto:maipc-bounces at lists.maipc.org] On Behalf Of Judy Fulton
Sent: Thursday, March 22, 2018 12:05 AM
To: Jensen, Mary <kate_jensen at nps.gov>; Toni Bailey <toni at gracefullygreen.com>
Cc: MAIPC at lists.maipc.org
Subject: Re: [MAIPC] groundcover suggestions

HI Toni,

I have concerns about this Ernst "Right-of-Way Native Woods Mix w/Annual Ryegrass" because it contains some potentially invasive species and cultivars. Also, it includes aggressive plants that I don't consider a temporary fix for keeping out weeds. Instead, depending on how much sun your shady site gets, they might crowd out less aggressive species. Here are comments on some of the species in this Ernst mix:

*	Lolium multiflorum syn. Lolium perenne ssp. multiflorum (annual ryegrass) is a non-native profuse seeder considered invasive by West Virginia. According to CABI: "L. multiflorum is a highly competitive and rapidly growing plant, capable of producing large quantities of seed. It is genetically diverse and displays a high degree of phenotypic plasticity and these characteristics mean that is highly adaptable. It can invade natural grassland and other plant communities that are subject to frequent disturbance." I really don't know why it is still included in commercial mixes.
*	Although the straight species of Panicum virgatum (switchgrass) is native, it is a strong competitor and not suitable as a temporary fill-in to prevent weeds. Moreover, the Ernst mix contains the cultivar 'Shawnee'. There are two potential issues with using a switchgrass cultivar: 
-  I don't know the characteristics of 'Shawnee', but many P. virgatum cultivars are bred to be more aggressive for conditions such as roadsides where quick establishment and coverage are desirable. That said, a mitigating factor to switchgrass' aggressiveness might be the shadiness of your site. 
-  Cultivars have little genetic diversity, and are at risk for damaging native populations through cross-pollination.
*	Panicum clandestinum, 'Tioga' (deertongue) is also a cultivar, so has the potential to damage wild populations. Besides, the USDA describes 'Tioga' as having strong rhizomes and abundant seed.
*	Festuca rubra (creeping red fescue) is probably a combination of native and introduced in Maryland, and is sometimes used in lawns. Would you want a rhizometous grass mixed in with your plantings?
*	Chamaecrista fasciculata (partridge pea) is an attractive native annual that prefers sun, and can spread aggressively from seed. 
*	Carex vulpinoidea (fox sedge) is a  somewhat weedy native that likes wet areas.

To summarize, I'm not sure that this seed combination would be appropriate for you based on your stated goal although your shade (partial shade?) might keep the more aggressive plants under some control. In fact, I can't say what species would work best for you because I don't know the growing conditions at your site (e.g., degree of shade, moisture level, soil type). 

I'd recommend one or more straight-species natives, that aren't overly aggressive. For example, Danthonia spicata (poverty oatgrass) could be used as a fill-in if the soil at your site tends towards poor, dry and rocky. Also, would you consider the more expensive option of plugs instead of seed? If so, there are a lot of woodland sedges that are deer resistant and are good choices if they work for your growing conditions, such as Carex pensylvanica (Pennsylvania sedge), C. radiata (eastern star sedge) and C. glaucodea (blue wood sedge -- note this is not the same as C. flaccosperma).  Another possibility, if you have the budget, is just to fill in spaces around the existing plants with plugs of the same herbaceous species you've already chosen. In any case, you might want to avoid using: (1) compost because it can encourage weeds due to increased soil fertility, and (2) mulch because it can inhibit spread of the existing plants through seed germination.

Please let me know if you have further questions.

Judy
____________________________________________

Judith P. Fulton
Consultant & Educator, Native and Invasive Plants
Master Gardener, University of Maryland Extension
Chair, Maryland Invasive Species Council Subcommittee on Invasives Lists
410-337-3701
jfulton5 at gmail.com <mailto:jfulton5 at gmail.com> 

On 3/19/2018 8:00 AM, Jensen, Mary wrote:

Hi Toni,

At Valley Forge NHP we used this mix from Ernst:

https://www.ernstseed.com/product/right-of-way-native-woods-mix-wannual-ryegrass/?anchor=0

to re-seed a social trail that we closed.  So far, seems to be  working.

But not sure about deer, Valley Forge has gotten them down to about 30 per square mile...  Maybe Ernst can let you know if this would still work if your deer are higher density, or maybe they have some other options.

**************************************************************
Kate Jensen

Mid-Atlantic Exotic Plant Management Team Liaison

Shenandoah National Park
3655 US Hwy 211 E
Luray, VA 22835

540 999 3500  x3496

FAX  540 999 3693

 <mailto:kate_jensen at nps.gov> kate_jensen at nps.gov

P Please consider the environment before printing this email

On Fri, Mar 16, 2018 at 12:10 PM, Toni Bailey <toni at gracefullygreen.com <mailto:toni at gracefullygreen.com> > wrote:

Hello All:

I am working with a shady slope near a natural area in Montgomery County, MD that was planted last spring with a combination of native trees, shrubs, ferns, and flowering perennials. Like everywhere, the deer presence is heavy. We are considering seeding this spring with a groundcover that will establish easily and keep the weeds at bay until the other plants fill in.

Does anyone have suggestions for things that work well in these conditions?

Thanks so much for your help!

Toni Bailey

Toni Bailey

Gracefully Green, LLC

Sustainable Landscape Specialists

Silver Spring, Maryland   20910

voice:  301-279-0234

fax:     301-279-0134

www.gracefullygreen.com <http://www.gracefullygreen.com/> 

 <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> 

Virus-free.  <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link> www.avast.com 

_______________________________________________
MAIPC mailing list
MAIPC at lists.maipc.org <mailto:MAIPC at lists.maipc.org> 
http://lists.maipc.org/listinfo.cgi/maipc-maipc.org

_______________________________________________
MAIPC mailing list
MAIPC at lists.maipc.org <mailto:MAIPC at lists.maipc.org> 
http://lists.maipc.org/listinfo.cgi/maipc-maipc.org

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.maipc.org/pipermail/maipc-maipc.org/attachments/20180322/ed4f91b5/attachment-0001.html>