What to notice outside around Sudbury in May
18 things from the field guide you can notice around Sudbury in May.
Sky
- Why you can see the moon in the daytime skyThe moon spends almost as much time up in daylight as at night, and on the right days it sits plainly in the blue sky.
- Sundogs and sun halos: how ice crystals bend sunlightIce crystals high in the atmosphere can bend sunlight into a pale ring around the sun or bright patches on either side of it.
- Crepuscular rays: sunbeams fanning out near sunrise and sunsetWhen broken clouds and haze meet a low sun, bright and dark bands can fan across the sky near sunrise or sunset.
- How the sunset point moves along the horizon through the yearWhere the sun sets on your skyline slides north through spring and south through autumn, fastest near the equinoxes and nearly still at each solstice.
- The Big Dipper never sets from eastern MassachusettsFrom eastern Massachusetts the Big Dipper is circumpolar, circling Polaris once a day, though the tip of its handle skims the horizon at its lowest.
Weather
Birds
Insects
- How water striders stand on a pond's surface without sinkingWater striders stand on the surface film of eastern Massachusetts ponds on water-repellent, hairy legs, denting it into dimples without breaking through.
- Moths at the porch light on warm summer nights around SudburyA single porch light on a warm, still night draws a small sample of the many moths already out in the dark around a Sudbury yard.
- Luna moths at the porch light, most likely in JuneAdult luna moths never feed and live only about a week, so one resting at a Sudbury porch light is a brief, lucky sight, most likely in June.
Mammals
- Big brown bats hunting over yards at dusk in eastern MassachusettsThe most common bat in Massachusetts suburbs, the big brown bat, leaves its roost in the evening to hunt insects over yards, ponds and field edges.
- Beaver signs: chewed stumps and pale wood chips along pond edgesBeavers work mostly at night, so pointed stumps, pale wood chips and paired tooth grooves along a pond edge are often easier to find than the animal.
Fungi
- Why lichen turns bright green after rainRain turns a lichen's gray outer layer see-through so the green algal partner shows, while lichens with cyanobacteria go dark green, brown or black.
- Black knot on cherry trees: the black lumps are a fungusHard black swellings on a roadside cherry's twigs are black knot, a native fungus, not fire damage or an insect gall, and it can keep growing for decades.
Amphibians
- Spring peepers: the tiny frogs behind the spring wetland chorusFrom the first mild evenings of March into May, male spring peepers small enough to sit on a quarter chorus from wetlands across eastern Massachusetts.
- Fairy shrimp swimming upside down in spring woodland poolsFairy shrimp are inch-long crustaceans that swim on their backs in woodland pools that fill each spring, hatching from eggs that sat out the dry months.
Landscape
- Stone walls in the Sudbury woods and the farms they once edgedAlmost every stone wall in a Sudbury woodlot was a field or pasture edge, built of glacial stones farmers cleared between the Revolution and the Civil War.
- Kettle holes: ponds and hollows left by melting glacial iceSome round ponds and deep hollows in eastern Massachusetts mark where a block of ice, stranded and buried as the last glacier retreated, slowly melted.