Friday, September 23, 2011

Hydrants can Water Trees

15 JULY 2011

WASHINGTON’S HOT SUMMERS hit sidewalk trees with a double whammy. Heat from the sun above bakes the leaves and dries the soil. The sun’s heat also bounces up from the pavement baking the leaves from below. So trees are cooked from above, cooked from below, while their growing medium dries out. Ouch!

So regular watering of young and vulnerable trees is crucial, especially trees in paved areas.

Each summer, Restore Mass Ave urges property owners to turn their hoses onto the sidewalk trees: 25 gallons each week, dripped slowly. Or to refill the bags we zip around the trees, which allow a slow drip from holes in the bottom. In the terrible drought of 2007, we paid for a truck to water about 120 city trees. (Thanks to your donations!)  We can’t be sure but believe that many of these trees would have died without this help.

Our Treekeeper volunteers work on hard-to-reach “orphan” trees, by dragging hoses hooked to nearby spigots. Sometimes they carry water-filled buckets in our red Flyer wagon to and from a parched tree.

Below see RMA Treeekeeper Sarah Randolph at work. (Photo: Restore Mass Ave)

This summer, fire hydrants will be our new rescue tool. We’re being loaned a Fire Hydrant Meter by the Dupont Circle Citizens’ Association on days DCCA doesn’t need it. The device (see photo) is a water meter and pressure converter; there is also a key for unlocking the hydrant.

The Fire Hydrant Meter measures the quantity of water used. It converts the high-pressure water from the hydrant to a low enough pressure for a garden hose – just right for helping a tree. (Trees should be given water slowly, so the soil and roots can to absorb it.) 

The equipment is heavy, so we tow it in our red Flyer wagon along the sidewalk from hydrant to hydrant. (DCCA tows it on a bike trailer.)

Thus our water-brigade can water the sidewalk trees which need water, with the amount they need, when they need it. 

Note:  RMA will provide this care on just few afternoons; the hydrant-watering is NO substitute for the main weekly water trees building owners should provide to nearby sidewalk trees.

See below for useful links for fire hydrant watering.

Recordall® Fire Hydrant Meter (Photo: Badger Meter)


Useful links

Note: To use a public hydrant for tree-watering, you must obtain a Fire Hydrant  Use Permit from DC Water (WASA), a hydrant key and pay a deposit. The Meter measures water used, which you must pay for.  See

Casey Trees' summer crew also waters by-cycle. See



We thank Doug Rogers, chair of the DCCA Tree Committee, and Greg Zahn of DCCA for sharing the equipment and how to use it.  

Thanks also go to Washington Area Bicyclist Association (WABA) for the training class in using hydrants for tree-watering. Casey Trees inspired us all with their Water By-Cycle Cart it uses to be sure the trees it plants on city streets get enough water.

How you can boost city trees with leaf mulch

5 JUNE 2011

HERE’S ONE REASON trees in city sidewalks grow poorly: crummy soil that hinders root development. Think about it: the pavement around a tree blocks its fallen leaves from decomposing in the soil and feeding its roots, as happens in nature.

You can help sidewalk trees with a layer of decomposing leaves spread directly on the soil. There must be no barrier so the decomposing leaves can trickle down, so you have to pull away all grass and weeds from around the tree first. Think of the leaf mulch layer as a one-time treatment - First Aid for a stressed sidewalk tree. Afterwards you can bandage the site with a 3 inch layer of shredded hardwood mulch (just don’t pile it against the tree, please).

The mulch layer will make weeding and tidying the tree box easier for seasons to come. You’ll increase the chances of having healthier, bigger trees shading the sidewalk and street. Also, a tree with strong roots is less likely to be toppled in storms.

Image: Heart Views

“I struggled trying to grow up until I got leaf-mulched!”

Here are the steps Restore Mass Ave followed in our second leaf mulch project on June 4 and 5. We treated another 20 sidewalk trees, in addition to the 50 we treated last fall; in all we’ve helped 70 DC street trees this way. It seemed worth the work and relatively small expense to help these trees to live a few more decades!

Step 1: Weed a 9’x 4’ area around the tree so the soil surface exposes the flare where trunk meets the main roots. 

Step 2: Snip off any little surface roots; cut any roots “girdling” the base; both will weaken the tree.  

Step 3: Spread shredded leaf mulch over the soil; the new layer will be fluffy with a musty smell like tobacco.

Step 4: Cover the black leaf mulch with shredded hardwood bark mulch to outline a neat box. That’s the “bandage” everyone will see, which will be help against weed growth, mowers, and heavy loads.

Step 5: Stand back and admire your neatly groomed tree and box. Be glad that underground, the roots will be fed naturally for several seasons. Listen.

Maybe you’ll hear the tree saying, Thanks!


Below: We clear weeds and grass from the tree. (Photo: Restore Mass Ave)

Below: We dump black, fluffy leaf mulch on the exposed soil. You can see the flare where the trunk becomes the tree’s main roots. (Photo: Restore Mass Ave)



We recommend you employ a professional if you try to help a whole line of street trees. We found Leprechaun Landscaping LLC of Bethesda. Md. to be experienced and reasonable. 

Shredded leaf mulch is sold as Karbon® Leaf Mulch at Loudon Composting in Chantilly, Va. Some public parks departments, such as that of Arlington County, offer shredded leaf mulch to residents. To find out if DC offers mulch from the leaves it sweeps off our streets and parks, call the Mayor’s Service Line 311.

We thank Dr. Monica Lear of the DC Urban Forestry Administration for recommending we try this for city sidewalk trees. We thank also T. Davis Sydnor of Ohio State University, who devised this protocol.

Venezuela Plants 18 “Replacement Trees”

1 MAY 2011

IN MAY THE Embassy of Venezuela planted 18 new trees as replacements for a very large old tree it sought to cut down, to comply with the DC tree law.

This planting will extend the tree canopy over bare parts of the Ambassador’s residence at 2443 Mass Ave on the corner of Mass Ave and California Street. Fifteen trees were added to this campus, notably four new ‘Valley Forge’ elms that re-build the ‘second row’ by the Mass Ave sidewalk, and a tulip poplar at the corner. Behind the military office at 2437 California Street, three cherry trees were planted.

Below: The Embassy’s Clara Rodriquez and a new Chinese Lacebark elm (Ulmus parvifolia ) and Hackberry (Celtis accidentalist). (All photos: RMA)

Under the tree law, 18 new trees were required for the city to allow the Embassy to cut down an ash tree behind the military office that was 115 inches in diameter. The city asked Restore Mass Ave to advise on the new planting.

Under the tree law, to cut down a healthy “special tree” of 55 inches or greater, an entity – even a foreign mission – must agree to plant “replacement trees” whose “circumference inches” (CI) equal that of the tree to come down. Or they must pay into the Tree Fund.* How big is a 55” CI tree? Below a Restore Mass Ave Treekeeper shows you. 

Below:  RMA Treekeeper hugs a 55” circumference “special tree.” (Photo: Restore Mass Ave)

The Venezuela Ambassador’s residence is one of the loveliest campuses on Embassy Row. When it was built in the 1930s, the old-growth forest of Kalorama was left standing; so were the “second row” trees lining the sidewalk. As these older trees die, the bare land needs new groves.

Below: Two new ‘Valley Forge’ elms in a line parallel to the public sidewalk. (Photo: Restore Mass Ave)

Next door, with our partner Casey Trees, Restore Mass Ave has arranged more than 20 large-type trees at the

Overall, city land needs 2,000 more acres of mature tree canopy. On Embassy Row, everyone in the community is trying to help!



Trees were provided by Landscape Development Co., Woodbine, Md. 

* DC Urban Forest Preservation Act of 2002 can be downloaded through this page

** Useful aspects of the Tree law on RMA's website

Below:  RMA Treekeeper hugs a 55” circumference “special tree.” (Photo: Restore Mass Ave)

Below: The Embassy’s Clara Rodriquez and a new Chinese Lacebark elm (Ulmus parvifolia ) and Hackberry (Celtis accidentalist). (Photo: Restore Mass Ave)

Trees as Storm-fighters

1 APRIL 2011

ONE WAY THAT trees help cities: a neighborhood with lots of mature trees needs less maintenance of underground storm drains and tunnels.

Here are two storm-fighting trees Restore Mass Ave planted with our partner Casey Trees in March. In the foreground is a Northern catalpa (C. speciosa). Behind is a swamp white oak (Q. bicolor).

Above: Northern Catalpa (C. Speciosa) tree (Photo: Restore Mass Ave)

Don’t they look fragile? But thanks to care by the Church of the Pilgrims, which abuts this land, these trees will grow into big, spreading structures that lessen water runoff onto 23d Street (on the right) and down to Rock Creek.

That is why we planted next to Rock Creek valley. We’re especially glad that the Park Service gave permission for these trees, because after the planting, we learned that there will be a one- to two-year project to replace the underground pipes taking storm water down to the creek here.

The city’s old combined sewer and storm system (CSS) backs up in storms. In sudden drenching storms sewage etc., instead of flowing through the system to the Blue Plains plant, overflows into the Anacostia and Potomac rivers and Rock Creek. One outflow pipe is by this location.* As part of a pipe and tunnel upgrade that’s six year’s on, these deep old pipes will be replaced.

Billions of dollars in new tunnels and pipes isn’t the only way to get our watershed to meet federal standards (finally). Greenroofs and bigger sidewalk tree boxes can stanch the water volume burdening the system and lessen maintenance costs. So will more trees strategically planted in open land.**

Basta about sludge!

Below are the flowers of a mature catalpa tree, white and trumpet-shaped in showy arrays. Catalpas grow 40 to 50 feet tall and spread 20 to 40 feet wide. With large trees, about a third of all rainfall is caught by the leaves. The trunk takes up more, while the root system carries much of the rest down in the ground.

Above: Catalpa flowers (Photo:  Mvia45)

This is Nature’s plumbing, working for us.

*The CSO 36 upgrade is part of DC Water’s Clean Rivers Project.   Go to for updates.

**A report on how DC can lower system burden by greenrooves and trees is Casey Trees, Limnotech WASA (2008)



Thanks to the Casey Trees staff for this imaginative choice and arranging to plant on this site.

Thanks to Church of the Pilgrims, especially Ashley Goff, for maintaining these and other new trees near the church.

Welcome to Restore Mass Ave’s Tree Care Blog


ABOUT US: Restore Mass Ave is an alliance of residents, foreign missions, arborists and non-profit groups working to rebuild the tree canopy and historic landscape that made Massachusetts Avenue a world attraction in the early 20th century. Through outreach and education we attract participation by owners of property, one third of whom are foreign missions. We spread the teaching of experts to those in community and train volunteer Treekeepers. We aspire to be a model for creating green neighborhoods elsewhere.

We are a 501 (c) 3, supported by financial donations from the community and in-kind donations from service providers and nurseries. Casey Trees is an important partner for additions of new trees. The National Trust for Historic Preservation supports our Historic Landscape educational brochure and planting guide.

Above: Green lines show the streets we're trying to restore. (Photo:

We work closely with city and federal agencies such as the DC Department of Transportation Urban Forestry Administration, the DC Historic Preservation Review Board, and the Department of State.

The federal Historic Landmark and Historic Preservation Act of 1978 protects buildings and greenscape in our area, which falls in the Dupont Circle Historic District, the Sheridan-Kalorama Historic District and the Massachusetts Avenue Historic District. Trees on public and private land are protected by the DC Urban Forest Preservation Act.

Trees planted through Restore Mass Ave count towards UNEP’s Billion Tree Campaign which aims to add seven billion trees worldwide by the end of 2009. From Nairobi, Kenya, UNEP wrote “we endorse your undertakings.” The campaign’s Album even contains an article on our work!