Mowing Tips: How to avoid killing Eastern Box Turtles


Please document any Eastern box Turtle  sighting for CTDEEP; photograph the upper and undershell, and also the habitat. Note  note the date and location. The  DEEP reporting form can be downloaded from the Endangered Species Section of the DEEP Website.  The Turtle Crossing Program of the Quinnipiac River Watershed Association compiles turtle records from  central Connecticut, for CTDEEP.  We also educate citizens on conservation of the remaining Eastern box turtle populations, and erect “Turtle Crossing” signs,  as road kill is a major cause of death. For sightings south of Meriden,  please e-mail; for Meriden & points north,  e-mail


If you happen to live in an area, which still has this declining species, be especially alert while mowing. Mower operators should be familiar with box turtles. Refer to photos of color and pattern variations, such as yellow, orange , tan, or mostly dark (small designs).  Photos are on-line.

Lawns should be kept short enough that turtles can be easily seen (< 4 inches)

Fields and brush should be cut when turtles are least active

Avoid mowing when temperatures are pleasant; instead mow when weather is hot and dry, when turtles are likely to be resting in the in the shady edges of fields or under shrubs, rather than in a hot, open area.  In summer, the highest risk period is the morning hours when there is still dew on the ground. During the hot, dry conditions typical of midday, turtles usually rest in the shade.  During prolonged hot, dry spells, turtles often aestivate (bury themselves and become dormant) underground.

Brush hog field edges or managed open habitat in the mid to late winter, when ground is frozen or relatively dry. Turtles hibernate underground during winter months.

If mowing a field when turtles may be active is unavoidable, set height of mowing deck to 6-8 inches. Although adult eastern box turtles reach no higher than four inches with necks extended, under certain conditions 8 inches clearance is wise: if ground is uneven or rocky or if mower has rotating blades such that suction can draw turtles up into the cutting zone. Uneven ground can elevate turtles into harms way. Probability of injury is very high for a flail-type mower with a deck set lower than 6 inches; risk is moderate for a haying cutterbar (attached to side of tractor.)

When closer mowing (lower than 6-8 inches) is unavoidable, we recommend these precautions: Use a hand-held string trimmer, which would not injure a turtle fully within its shell.
For larger areas, have someone walk in front of the mower to check for box turtles. Any turtles found should be moved several hundred feet out of the way. Do not relocate turtles off site.

Leave strips or “islands” that are infrequently cut, such as a 3 to 8-foot wide swath of meadow or shrubs between the lawn and the woods edge; beds of shrubs and perennial wildflowers with wood chips; or a meadow-wildflower patch. Turtles will spend more of their time in these areas, feeding on insects and worms, than in the open lawn or field, and they improve the overall habitat quality. Woodchips are a preferred refuge in the heat of the day. Avoid broadcast pesticide use in these areas.

Note that fields over three acres in size are likely to support nesting by rare and/or declining grassland birds species. These are best protected by not mowing at all from May 15th to August 15th .

Developed for the Quinnipiac River Watershed Association’s Turtle Crossing Project by ecologist Sigrun N. Gadwa of Carya Ecological Services, LLC, Cheshire, Connecticut. Advice provided by Dan Rosenblatt, Regional Wildlife Manager for State-owned Lands in Long Island, Stony Brook office of the New York State Department of Environmental Conservation; herpetologist Hank Gruner; professional mower James Hutchinson of East Haddam; Blake Wilson of Ships Hole farm, Smithtown, Long Island, NY, and others. Photos by Tony Ianello. Layout of first edition by Illisa Kelman. January 2007. Revised June 2013.

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Water Woes on Drumlins

Water Woes on Drumlins

What is a drumlin anyway?  A gremlin with an aptitude for percussion?   Seriously, a rounded, elongated hill in the Connecticut landscape is probably a “drumlin”. The best known is Horsebarn Hill on the eastern side of the UConn campus at Storrs. Landing Hill in East Haddam was  in the local limelight several years ago. Lately I’ve been working on Meetinghouse Hill and Misery Hill in Franklin.  The Goshen Wildlife Management Area is another. The word “drumlin” comes from Ireland, where this land form also occurs.

The core of a drumlin hill is fine-textured, compact glacial debris, though bedrock may be underneath, poking through in a few places.   The compact “hardpan” layer (in common parlance)  may be over 100 feet thick, and dates from the prior Illinoisan glaciation (over 128,000 thousand years ago). Only the top layer, usually just a few feet deep, is sandier, looser soil, formed from the melting ice masses of the more recent Wisconsin glaciation, underlain by the compact till (scientists’ terminology).

These soils are seasonally wet.  Though the level summits seem, at first glance, to be well-suited to community development, they are challenging to develop, whether on drumlins or elsewhere, such as plastered onto the sides of traprock ridges. Most gently sloping drumlin hilltops in New England used to be productive hayfields, growing lushly in spring when soil moisture was available, going dormant in mid summer.  Pockets of wet meadow were rich in flowers, like New England Aster. Drumlin fields make fine hunting territories for raptors like barred owl.

Colorful wet meadow perched on top of drumlin.

Multiple seasonal seepage wetlands and headwaters streams flow down drumlin hillsides. They are a valuable source of clean water for the drainage basin if the drumlin is undeveloped, they but may become conduits for construction runoff.

There is more groundwater discharge on the nearly level sections of drumlin hillsides than on the steep sections. These are also prone to septic breakout.

Only a small percentage of Connecticut’s soils are compact tills but a disproportionate share of construction site fiascos and problem-plagued new subdivisions occur on hardpan soils. Wet, silty, sticky  hardpan  soils, on drumlins and also in other landscape settings,  can become a mire for heavy construction equipment because the snowmelt and spring rains “perch” on top of the hardpan. Saturated silty soils are highly erosive,  often an erosion control nightmare. Flooding problems are more severe than on absorbent soils, and water pollution from lawns and septic systems becomes a problem at lower home densities.  Break-out from home septic systems happens more often.

Typical complaints of drumlin residents: wet and moldy basements, icy sidewalks;  soggy, fungus-infested grass, burned-out grass, and dying shade trees; extended sump pump operation (not energy efficient), mosquitoes, and septic odors; and polluted down-gradient ponds.  These all become more of an issue for seasonally wet, drumlin soils, because more water stays at the surface, as it cannot soak into dense hardpan soil. (Runoff coefficients are higher, in engineering jargon.)

With careful home and septic system placement, curtain drains, and appropriate landscaping, one can avoid some of these problems – but only if home densities are relatively low.

Ironically, the loose upper soil layer of a drumlin is usually so shallow that it holds little reserve water during dry spells, so drumlin lawns need much irrigation in summer, though excess water is the problem in other seasons.   Solutions: small lawns, partially wooded yards, and/or a meadow landscape with drought-tolerant grasses like Little Blue Stem, a.k.a. Poverty Grass.

A Plea for Guidance

Could  CTDEEP and our Conservation Districts provide land use boards, planners, and developers  with more guidance on drumlins’  multiple constraints?  On-line mapping (Web Soil Survey or WSS) available from the Natural Resource Conservation Service (NRCS) does show the approximate locations of seasonally wet, hardpan soil units, like the Paxton, Woodbridge, and Wethersfield soil series.

More guidance is needed to make sure fertilizers and pesticides are not applied before or after heavy rains.  This happens all the time in Connecticut suburbs!  Turf chemicals tend to run off drumlin soils, more than off more absorbent soil types, especially when the soils are already soggy.

Few understand that watercourse setbacks often need to be wider and  septic system densities need to be lower on compact till soils, to protect down gradient wells, headwaters streams, pools, and lakes from excessive nitrogen,  in nitrogen enriched groundwater and runoff. Because they reduce lot yields, these constraints need  explanation in an official DEEP guidance document, preferably also in a  CT Health Department memorandum!

Clear-cutting may seem to be  more economical for the developer, who should be warned that this is not wise on a drumlin!  To minimize future “water woes”,   maximize  remaining tree cover when subdivisions are built. The reason is two-fold: 1) to slow the velocity of the falling rain, and 2) because trees spew thousands of gallons of water into the air as water vapor (transpiration), helping dry out those surface soils.  After clear-cutting, a drumlin hillside that used to be wet only in March and April may stay wet to the surface though June – and before long, one will see the tell-tale mottles and grayish matrix color of a jurisdictional Connecticut wetland soil.

Some, but not all engineers use underdrains and clay stops  to prevent frost heave damage to roads and utility pipes, and to allow shallow groundwater to continue to seep down slope to wetlands that depend on this water source – instead of being shunted along  roadbeds and sewer lines.  Guidance is also needed in this area.

Once aware of drumlins’ constraints and resources, town  zoning boards  will be able to  guide development more appropriately,  protecting valuable vernal pools and hillside streams, and at least a portion of the productive forests. For expansive overgrown fields on flat-topped drumlins, if the alternatives of farmland or grassland wildlife habitat are not possible, at least the damage to down-gradient headwaters resources,  from a  low density, large-lot residential community, with small lawns,  will be  much less than from a large, dense subdivision.


(First version of blog posted on 9-6-08)

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The Red Menace

Euonymus alata, also known as burning bush, is at least a clear-cut villain, unlike  some of the other invasives.    I recall spending a long June day collecting vegetation data in an an immense Euonymus thicket, a former estate  in Wilton. I did not even  observe a catbird, the most common thicket songbird in Connecticut! And beneath the dense bushes, the ONLY plants growing were Euonymus  seedlings.

This species must have high-powered chemical defenses. The glossy leaves look almost artificial (and might as well be), no holes where caterpillars or leaf beetles have nibbled.  Pickings are slim for foliage-gleaning parent songbirds.

Euonymus everywhere, east slope of Peck Mountain. (Sorry I have no shots of the sea of red in fall)

Euonymus alata, from Asia,  is an effective invader of forests, because it grows well in shade, unlike bittersweet, multiflora rose, everlasting pea, and Phragmites. It spreads well by runners as well as seed. Unfortunately, it thrives especially in the mineral-rich, sub-acidic  soil of traprock ridges.  Because suburban yards on the flanks of the ridge provide abundant seed sources, Euonymus has overrun much of Peck Mountain, in north Cheshire.  Formerly diverse and special  traprock vegetation communities have become burning bush monocultures.  Euonymus is even able to thrive in specialized traprock habitats like ledges and talus. Some rare Staphylea trifolia  (bladdernut)  and marginal wood fern remains on the west slope  of Peck Mountain, but not very much. Connecticut nurseries are still battling the environmental regulators, to prevent an outright ban of Euonymus alata, because this is such a popular, lucrative species for  the landscaping business.

Even grows well on traprock ledges

After that Wilton experience and an eye-opening hike on Peck Mountain,   I knew we had to get rid of the burning bushes in our own yard. Emotionally, it was not so easy.  This is a beautiful shrub, especially when crimson in the fall, and it makes a dense, tidy hedge.  The wings or flanges on the stems also look interesting in winter.  Our bushes had special meaning because they been given to us by relatives who were dear to us.

Control  was very quick and simple, from a practical standpoint. We snipped them with a lopper, and painted the freshly cut stems  with Brush-B-Gon (8% triclopyr). For those who simply cannot kill their prize burning bush, thoroughly shearing off the seeds each September, with hedge clippers,  will at least prevent further spread by birds.

For illustrations and discussion of other invasive plants, see the accompanying facebook album “Invasives????” (Sigrun Gadwa)

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Origins of the Traprock Ridges

The extensive ridgetop hiking trails in central Connecticut are fairly well known, with their fine views, blueberries, and sunflowers, e.g the trails on East Rock, West Rock, Mount Higby, the Hanging Hills,  Cathole Mountain, and Ragged Mountain.  However, remarkably few people who live here realize that the Metacomet and other ridges are  of volcanic origin.  Why isn’t this  part of every high school earth science  class? The geologic processes described below have created a rugged landscape with mineral-rich, subacidic soil,  steep slopes, talus (fields of basalt chunks), cliffs, and exposed rock outcrops;  these are all habitats for unusual flora and fauna, including rare species – another fact that is not widely known.

View from the southwest of Cathole Mountain (south end of the ridge, in  Meriden)

Connecticut does not have cone-shaped mountains that once rumbled and spewed ash and lava. Instead the lava oozed more slowly from deep, elongated cracks, that started forming 200,000 years ago, when  the supercontinent, Pangaia, began to pull apart.  Tension between the freshly separated continents caused two elongated cracks (faults) to form. The land settled between two deepening faults, creating a rift valley.  Molten lava oozed up through the deepest cracks and spread across the valley, and then cooled and hardened into traprock (basalt). Three separate periods of lava flows formed three beds of variable thickness.  The middle bed (Holyoke Basalt) may be hundreds of feet thick.

The valley gradually filled with sediment eroded from what used to be high mountains in eastern and western Connecticut. The eastern and western highlands are still many hundreds of feet higher in elevation than the lowlands of the Connecticut valley.  Each successive bed of basalt (cooled lava) was buried by sediment that was compressed into a reddish-brown sedimentary rock, known as brownstone or New Haven Arkose. Total deposition was two miles thick at the Eastern Border Fault in Middletown.  Climate conditions at that time were tropical, which accounts for the red, oxidized color of the sedimentary rock and its low mineral content.[1]

Because the rift valley was still deepening along the Eastern Border Fault (often called the “trapdoor”), the rock beds all tilted down to the east, by 15 to 25 degrees.  The broad basalt beds were glued together by sedimentary brownstone.  Eventually the beds  broke apart into multiple, tilted  “sandwich” chunks.  Over time, especially during the periods of glaciation, the  process of erosion exposed the higher, western, “up-tipped” edges of the these basalt beds, since  traprock is considerably harder than brownstone. The sedimentary“glue” weathered away between the layers of basalt rock. The western edge of each broad basalt slab became a basalt ridge.  A traprock ridge  typically has cliffs and steep talus fields on the west side, and a gently sloping eastern slope,  corresponding to the original easterly tilt of the rock formation.

 The ridges often show an interesting triplet pattern: a central taller ridge corresponding to the thick bed of Holyoke Basalt, is flanked by two much lower parallel ridges, corresponding to the thin slabs of Talcott and Hampden Basalts).  The far north end of Cathole Ridge shows this pattern very clearly.

Most of our  traprock ridges originated as described above, from the western edges of cracked, tilted  lava slabs. However, some “intrusive” formations like Sleeping Giant and West Rock[2] were formed underground. The oozing lava cooled slowly underground, rather than on the surface. In this slow-cooled rock, called diabase, crystals are larger and visible to the naked eye. The  rock weathers more slowly, but mineral composition is identical to basalt. These intrusive ridges were buried by sediment and then exposed by weathering and glacial scour, just like the basalt ridges.

Central Connecticut’s  continuous, above-ground traprock ridge system extends northerly into Massachusetts, but cracks in the rift valley oozed lava as far north as Newfoundland.  Intermittently exposed basalt also occurs in Newark and Hoboken, New Jersey (the Palisades) and further west in the Pomperaug valley in Southbury and Woodbury, Connecticut.

The sub-acidic, volcanic soil on traprock ridges is fine-textured and less acid and richer in minerals, like calcium, magnesium, and potassium- than soil derived from brownstone, granite, gneiss or schist.  Second, the thin soil, rocky outcrops, talus,  boulder fields, and steep slopes are specialized ecological conditions quite different than that found in lowland forest, and are associated with a unique suite of plants and animals.

Partly open glades are characteristic, The “lawn” is actually Pennsylvania sedge, which remains low, naturally. A characteristic suite of plants (besides Penn Sedge) grows in this habitat.

These ecological communities have been designated  as high priority “critical habitats”  by CTDEEP.  However, like  the low public awareness of the ridges’ unusual volcanic origins, public awareness of the traprock ridges’ high conservation value seems surprisingly low, even in the towns where the ridges are major landscape features, like Meriden, Berlin, Cheshire.  and New Haven.


[1] An infertile “tropical” soil with a reddish color forms from brownstone parent material unless it is enriched by basalt glacial till or by river sediment.   The well weathered soils of the tropics are also known for their red color.

[2] The name of West Rock (in West Haven and Hamden) changes moving northward, first to Prospect Ridge,  and then to Peck Mountain in North Cheshire.

(See also my two fb photo albums on Traprock Natural Resources)

Sigrun N. Gadwa MS

Ecologist, Soil Scientist

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Rose Maze

Yesterday at dusk I was near downtown Wilton, at the site of a future apartment building.  I was trying to get out of  an approximately  2-acre thicket of invasive shrubs and vines, after characterizing them. It was raining hard, so I was clutching my glasses, trying to protect my notebook. (Had not put on the uncomfortable rain jacket, as it wasn’t raining yet when I started my field work.)

Five times I painfully pushed towards the outside, only to reach either a chain link fence, a truly impenetrable mound of multiflora rose, or a pile of logging debris – so I retraced my steps. I prayed on and off, felt like Tom Sawyer trying passage after passage in the cave. Or Sleeping Beauty, having woken up on her own, trying to escape through the thicket of roses that had grown up around her palace.  I remembered another consulting job site:  a tall, impenetrable multiflora thicket surrounding  a small  farmhouse occupied by an elderly  widow. Mowing had ceased when her husband had died.

Eventually, a patch of stately, thorn-free Japanese knotweed (like bamboo) was my gateway to the road and safety, my “prince”. I am so grateful to this grove of invasives, although Jap. knotweed is one of the most villified.

Growing up, I always thought of this plant as a privacy hedge, because the womens’ outdoor shower at the Nissequogue Point Beach Club was shielded from the prying eyes of outsiders by a knotweed thicket. Half a century later, I returned to find the same cold shower and the same dense thicket with large heart-shaped leaves. What a persistent monoculture! Overtime the knotweed at the Wilton site might well replace the multiflora rose (that is if the apartments weren’t built). At least it’s handsome, with bountiful nectar, welcomed by insects in late summer, when pickings are slim elsewhere (before all the goldenrods are in bloom.)

This is the king of the clonal perennial species, and the hardest of all the invasives to eradicate. Even after aggressive herbicide application, sprouts will come up the next year … and the next.  The latest control technique is to drill a hole into  every  tough, hollow stem in the knotweed patch and then inject herbicide into the hole; repeat for three successive years.

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Milky Spore Mystery

In about 1990 we applied Milky Spore to our lawn, just once, in the fall, after several years of  trapping Japanese beetles  in funnel shaped plastic bags with flower-scented lures. I’ll never forget the sickly sweet smell after it rained,  and the dead beetles started decomposing! Milky Spore Disease was outstandingly  effective, already the following summer. Over the past 20 years it has been rare to spot even one beetle.

Then why do I keep hearing  reports of failures from various people? We even received a refund from the mail order company the next year, as many people had reported failure. How were their lawns different from ours? I wish a research agency would do a systematic study! In the meanwhile, perhaps internet comments can begin to solve the mystery.

Gadwa Case in Cheshire CT.

1: Our  high beetle population at the time of application must have allowed an initial build-up of high spore concentrations.

2. We live on an exposed  ridge top in central Connecticut – Hardiness Zone 5b.

3. We had used no herbicides or insecticides, but  some  chemical fertilizer (granules about once a season), and had initially added much composted cow manure & peat moss to our four year old lawn.

4. Our soil was a stony, well-drained fine sandy loam (largely subsoil, stripped of topsoil when the house was built), derived from glacial till, sunny in 1990.

If it were only clear how to make Milky Spore Disease work, I’m sure this natural one-time control would be preferred by most to repeated applications of  long-lasting broad spectrum neurotoxins, such as  imidacloprid!    Imidacloprid  is toxic to ALL insects, be they pests or  benign, and harms human health as well.  It  has a half life of up to 730 days, and migrates through the soil.  Imidacloprid is the active ingredient in  Merit, Preen and Bayer Advanced, among others. The new formulation of GrubEx has Chloratranilipole, also a systemic, broad- spectrum insect neurotoxin, toxic to aquatic life – but with less risk to mammals (like us) and birds and somewhat less persistent.

Comments on others’  experiences are very welcome!

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Far-Travelling Toxins


Sperm and bottlenose whales

Very High Toxin Concentrations found in Arctic Whales

The link  below is  an article sent by a colleague on the surprisingly high levels of toxins, found in arctic whales.   Concentrations of toxic heavy metals like cadmium and chromium, were orders of magnitude higher than the danger levels for human fish consumption.  At every step in the food chain,  a persistent metal toxin (slowly- or non- biodegradable) bio-magnifies (tissue concentration becomes higher).  Metals in road runoff that reach the ocean biomagnify in seafood.  Abroad in many countries, DDT, which persists indefinitely, like metals, is also still used.  Persistent toxins are also transported thousands of miles though the oceans, in currents- potentially the gulf stream-   and by wind-driven surface flows, and  also by migrating fish and whales.  (This is similar to the insecticide bio-accumulation problem  mentioned in my recent zigzag dogwalking post.)

Oil Toxins will not be contained in the Gulf

The take home message: not just the Gulf of Mexico and its  coastal marshes  are threatened by the Gulf Oil Spill, and that threat is not just in the distant future.

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