Many readers commented over the winter on the leaf damage that Sandy inflicted on many of our evergreens. Sandy’s hurricane-force winds carried salt mist far inland, and the storm’s lack of significant rainfall, which can often rinse plants clean before the salt does any harm, only compounded the situation.
Most readers expressed concern for the state of the salt-sensitive white pines, whose long, delicate needles turned a chestnut brown soon after the hurricane. This condition was found among nearly all white pines on the South Fork, even those well inland from the ocean or nearest bay.
As with all evergreens, leaves do not remain on the tree for more than a couple of years. Over time, the leaf’s ability to capture sunlight and photosynthesize is compromised by damage to the solar collector’s surface and shading from newer, better-positioned leaves. Eventually, the leaf becomes more of a liability than an asset to the plant, and it is discarded.
Once a white pine’s leaf reaches three years of age, its reusable compounds are absorbed and recycled, and the leaf is shed. This means that white pines drop approximately one third of their leaves every year.
Unlike the short, several-month-long lifespan of our deciduous leaves, evergreen leaves are constructed to function over several growing seasons. One of their key longevity features is a thick, protective, waxy coating over the leaf surface. This coating varies among species, resulting in different tolerances to salt spray among our native evergreens: white pine being at one end of the spectrum, and pitch pine and eastern red cedar positioned at the other.
While designing a new segment of the Paumanok Path on the ocean bluffs at Montauk Point some years ago, I was surprised to find quite a few American hollies interspersed among the wind-sculpted, bluff top vegetation. Its relatively large, broad leaf seemed ill-suited for coping with the constant salt-laden winds found there. Perhaps this particular species of holly has an extra thick layer of protective wax. And perhaps the cost of that layer is a reduced rate of light transmission into the leaf’s chlorophyll, and lower rates of photosynthesis, as the American holly is one of our slowest growing native trees.
A close, careful, post-Sandy look at the white pines revealed that their east-facing sides were most affected, while the needles on their west-facing branches were largely intact and green. My guess was that there were enough healthy leaves to sustain the pines through the growing season.
One question that remained unanswered until recently was, “Were the white pine’s leaf buds damaged by the salt spray?” Unlike leaves, buds do not photosynthesize and, therefore, are not limited to a certain thickness of protective wax. Buds are generally much more resistant to drought, wind damage and salt spray than leaves.
The white pines I inspected in late May had healthy leaf buds in the process of sprouting new leaves. But inspections of the seaside plants revealed that even buds have their limits. Eastern red cedars growing within 100 feet of the high tide line on east-facing bay beaches lost both leaves and buds on their bay side.
A visit to many coastal areas over Memorial Day weekend found most of our coastal plants thriving, a testament to their resilience. Even the small, stunted American beech growing at the bay’s edge at Barnes Hole Road sported a few green leaves.
Memorial Day weekend was one of the coldest, and windiest, I can recall. The stiff northerly winds that blew all day Saturday and Sunday pushed the unseasonably cold, mid-50-degree ocean water offshore, and replaced it with even colder water that hovered around 50 degrees Monday morning. By late afternoon on Monday, a strong southwesterly pushed some of the warm stuff back inshore, raising the water temperature to 54 degrees but casting a big chill over the beach.
It seems we’ve had a lot of extremely windy days this past winter and spring, much more than usual. I’ll have to consult our master weather recorder, Richard G. Hendrickson of Bridgehampton, to see if he can confirm that.