Calendar of Events

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Water Quality Testing this summer
Friday May 20 at 10am: Volunteers needed for biweekly Water Quality Testing May – Sept. Attend the virtual training session and join in the effort to track and understand the water quality of Sligo Creek and Long Branch! Sign up at the Anacostia Riverkeeper Eventbrite page.



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PAST EVENT: Stormwater Challenges in TP

FOSC co-sponsored the Takoma Stormwater Solutions Webinar. Takoma Park stormwater experts and advocates discussed the challenges in controlling rainfall runoff and preventing household flooding. The resources and video are posted on the TSS site.


PAST EVENT: Trash Action in the MD Assembly

Shari Wilson, Interim Executive Director of Trash Free Maryland, briefed us on the trash and litter reduction bills in the Maryland General Assembly this session, including where lobbying might have the greatest impact.

PAST EVENT: How’s the Water? Results of the Summer Water Quality Testing Program in MD

Water Quality continues to be a challenge overall in Sligo and its tributaries. But there are areas that are improving. See the weekly results of the summer testing program in Sligo on the ARK/FOSC Volunteer Water Quality Monitoring Data page. The just-released Final Maryland Summer Volunteer WQ Report is also on that page, and on the Anacostia Riverkeeper website. View the video of the event at this link.

PAST EVENT: Meet Chris Williams, new President of AWS

Chris Williams, the new president of the Anacostia Watershed Society spoke about his vision for the Watershed, including Sligo Creek. View the videothe passcode to the video is: Z?4Z64tU

PAST EVENT: “Migratory fish in Sligo?”

July 20, 2021 – Phong Trieu of the Metropolitan Washington Council of Governments Anacostia Program described his findings and observations about the migratory fish entering Anacostia watershed tributaries in recent years. View the video of the talk:

PAST EVENT: “Bird Outing”


June 19 -Bird outing with Dave Blockstein and Mary Sanger.

PAST EVENT: “Cicada Party”

June 5 – John Lill, Biological Sciences Dept chair at GWU, and Diane Lill, Greenkids Program Director at the Audubon Naturalist Society, led a walkabout at the Sligo MS baseball field. About 50 people joined John and Diane as they illuminated the intricate lives of the cicada subspecies participants found onsite. Check out the story and photos on the Natural History page.

PAST EVENT: Bird Outings

May 14 – Bird outing with Dave Blockstein & Mary Sanger.
May 15 – Bird outing with John Stith

PAST EVENT: USGS Monitoring in Sligo – data and trends

Chuck Walker of the regional USGS MD-DE-DG Water Science Center spoke on the health and water quality of Sligo Creek. The Water Science Center has partnered with MoCo DEP to collect continuous water quality data on 7 parameters at the Maple Ave gauge. How is Sligo faring compared to other regional streams? Chuck discussed the long term trends and implications for Sligo as our area gets more densely populated. If you missed the event, check out the video on FOSC’s YouTube channel.

PAST EVENT: Urban Forestry in MoCo Parks

View the video of the presentation
Oct 27 – Urban forestry in ParksColter Burkes, Senior Urban Forester at Parks, led a presentation and discussion of tree management in Moco Parks, plus green waste recycling, and hazardous tree management.

PAST EVENT: “Spotlight on Native & Invasive Vines of Sligo / Virtual Tour of Sligo Meadow & Restoration Projects”

Ever see vines looping and climbing from tree to tree in Sligo? What makes these 3 native vines – Native grape, Virginia creeper, and poison ivy – so important to Sligo Creek and park? Food and shelter for wildlife and the fact that they do not strangle the trees they climb on, explained Corinne Stephens, director of MoCo Parks’ Weed Warrior program.
In contrast, Non-Native Invasive (NNI) vines bind trees and eventually kill them. The 8 Non-Native Invasive vines that Weed Warriors are authorized to remove from Sligo are:

-English Ivy
-Japanese Honeysuckle
-Oriental Bittersweet

Corinne’s presentation shows photos of these NNIs. Please pull them from your yard!

Dianna Loescher, Senior Natural Resource Specialist at Parks, led a virtual tour of the Sligo meadow and restoration projects, highlighting the techniques and plantings that are working and those that have been revised as site data is gathered. Check out her presentation here.

Our thanks to Corinne and Dianna for great presentations!

PAST EVENT: “Less Lawn, More Life”

Merikay Smith, of the Master Merikay Smith of the Muddy Branch Alliance and Master Gardeners Speakers BureauGardeners Speakers Bureau and the Muddy Branch Alliance board, described the process of converting her lawn into a native plant habitat that supports a diverse array of wildlife. Her neighbor joined in, converting parts of their lawn too.

She recommends starting by assessing what you have already – is it native or not, is it a non-native invasive or not? Take out the non-native invasives first! Some other elements of a habitat to incorporate are:

Plant a full stand of a native – too little and birds who are attracted to nest near it are unable to feed their young for lack of food (chicks don’t eat seed, they eat caterpillars or other insects, so plant enough so there are insects to feed the brood.)

Put a water source – can be a simple dish you pour out and replenish every few days.

Make changes by starting with the corners, and then the edges of your property.

Start in a corner(s) by planting a native tree – these are the circles on a plan. Oaks are superstars. For example, a Black Jack Oak supports 500+ species of insects

Then connect the circles with beds along the edges.

Site prep – build beds by covering a lawn area with cardboard, then compost and mulch, in the fall. Don’t dig!

Fully research the species / cultivars you plan to plant since many seem native but aren’t genetically native and a host for local insects.

Get recommendations by zip code through the National Wildlife Federation’s Native Plant Finder and the Audubon Society’s Plants for Birds.

Focus on keystone plants – those that sustain the food web of plants-insects-birds:

Keystone trees: White Oaks are superstars; Native Cherries, Native Willows, Native Birches, Cottonwoods, Elms

Keystone herbaceous plants: Native Goldenrods, Asters, and Sunflowers.

PAST EVENT: Improving Outreach and Inclusion

Our watershed is diverse in so many ways. We recognize that we need to reach out thoughtfully and more effectively to be inclusive of all Sligo watershed communities in outreach, programming and leadership.

On March 25, three leaders in the Black and Latino environmental movement discussed their perspectives on how Friends of Sligo Creek can engage the diverse communities living within the watershed.

(l to r) Ruby Stemmle, founder EcoLatinos; Raymond Coates, Community Outreach Coordinator, Ward 8 Woods and EarthJustice; and Dennis Chestnut, founder Groundworks DC, and Board, Alliance for the Chesapeake

Moderated by FOSC Advocacy director Kit Gage, the panelists discussed the importance of developing relationships with the communities who have been underrepresented in FOSC’s work; learning about the issues important to those living in the community; and tapping residents to develop and lead initiatives in those communities. A synopsis recording of the discussion is available below from the FOSC YouTube channel.

Improving Outreach and Inclusion March 25, 2021 event video on YouTube

PAST EVENT: How to use iNaturalist

Pine Siskins at Wheaton Branch Ponds by Stephen Davies

Heard about but uncertain how to navigate the site or contribute your own observations? Expert birder and iNaturalist contributor Stephen Davies recently gave a tour through the many features of this site. He used the iNaturalist project “Fauna and Flora of the Sligo Creek Watershed” as a starting point.

iNaturalist is an open-source, joint initiative of the California Academy of Sciences and National Geographic. It has world-wide scope, with 3.5 million people contributing 57.8 million observations to date.

Users can upload their observations, keep track of their photos, crowdsource identifications, join citizen science projects, see trends and build knowledge of the natural world. Creating an account at iNaturalist is simple and free.

FOSC also has a page on how-to-navigate-in-iNaturalist to help you find observations of interest and upload your own, as well as a page on how works.

To receive the Newsletter with all upcoming event invitations and meeting links, please join FOSC.

PAST EVENT: What’s in Sligo’s Water?

Membrs of the Water Quality committee – Anne Vorce, Pat Ratkowski, Paul Chrostowski – and guests Mike Smith, FOSC President, Elaine Lamirande from the FOSC Stormwater Committee, Kit Gage from the Advocacy Committee, and Rachel Gauza from the Park Dept’s Aquatics Resource Management office presented a fascinating glimpse into the state of water quality of Sligo Creek today and trends over time.

These speakers discussed many facets of Sligo’s water quality: pollution and the importance of FOSC’s citizen-powered Water WatchDog pollution reporting and tracking program, growing concern on microplastic and persistent chemical contaminants, sediment pollution, chemical and Coliform bacteria loads now and trends, macro-invertebrates in the Creek, the detrimental impact of the increasingly powerful stormwater events on Sligo, and FOSC’s Sligo advocacy work across many issues, including against a proposal for use of synthetic turf locally.

We then opened things up for questions, observations, and suggestions on Friends of Sligo Creek’s water quality program.

— The FOSC Water Quality Committee