Sunday, April 22, 2012

Coastal Alaska, Project BudBurst and Traditional Ecological Knowledge

Towns in Southeast Alaska are nestled closely to mountain slopes right next to the ocean. 
Just a short walk from downtown you can usually find lush forests, alpine meadows and wetlands 
- a great  place to learn natural history and to track the effects of weather and climate. A rich history of traditional uses of foods in this forest and along the shorelines may provide additional clues to how this area is adapting to climate change.

Alaska is a land of extremes and often seems to be out of synch with what is going on in the rest of the country. This past week I had the opportunity to be up in  Juneau to see how spring is progressing up there. In contrast to much of the country, coastal Alaska as well as much of the Pacific Northwest east to Montana has had quite a cool snowy spring and winter.  It is a cool rainforest so this time of year it can be green even before new leaves or plants appear in the spring. Mosses and lichens can grow in the winter or early spring so give the forest a lush green appearance.

Observations of phenology with Project BudBurst in Alaska are particularly valuable for scientific studies since this area has had a dramatic change in climate over the past 30 years. Glaciers are rapidly melting and avalanche paths are being colonized by tree seedlings.  You can easily see the changes. Here in Juneau I made weekly observations of plant phenology long before Project BudBurst began, back in the 1980's-1990's. Project BudBurst observations today can be compared with these historical ones to see not only how fast things have changed but also to see how consistent the change is between species or stages of plant development.

This year the spring is almost as slow as what we saw back in the late 1980's with early blueberry (Vaccinium ovalifolium) starting to bloom in the past week or so and western skunkcabbages in full bloom. Several forest plants are starting to leaf out such as salmonberry (Rubus spectabilis), red elderberry (Sambucus racemosa), and false lily of the valley (Maianthemum dilatatum).

In order to understand how much things are changing you need  a historical record to provide some basis of comparison. While attending a conference on Coastal Rainforest Ecology sponsored by the newly established Alaska Coastal Rainforest Center, I heard many interesting  presentations on the wide range of research being conducted on these unique forests. One point that was made several times was how closely connected the native tribes are to the seasonal cycles of plants in these moist forests.  The flowering of the skunkcabbage for example was used to determine the best times (often only a two week period) to harvest a special seaweed. When fireweed seeds start sending their cotton through the air is also a signal of a good time to harvest blueberries before they get infected by fly larvae. So many of these phenological events are used to look for subsistence harvesting, much like how observations of weeds or wildflowers is often used to determine when to plant seeds in agricultural areas. If we can start documenting the timing of these events this could be an important way to document changes in this forest. Are these plant phenology clues still an accurate way to determine when is the best time to harvest traditional foods? The Chugach National Forest is starting a new program in which observations of budburst are combined with nature walks. The Kenai National Refuge also has an active phenology program. More activities like this are needed to answer the many pressing questions of how plants in Alaska can adapt to the many changes occuring right now in this special place.

Today in Colorado it was over 70 degrees, with peonies, irises and other garden flowers beginning to come into bloom a month or more early. People are very busy putting in gardens and mowing lawns. What a contrast with Alaska!  The contrast between what you see here and the rest of the country is a great example of why it is important that Project BudBurst have volunteers  all across the country. Often it is the places that are the exceptions to the general rule that provide the key insights that may lead to new and important scientific discoveries. Only time will tell.

Paul Alaback

Photos (Courtesy of Paul Alaback)
View of Sitka area in Southeast Alaska.
Lush rainforest on Mount Roberts in Juneau last week. Only a few plants are sending out new leaves now, even at sea level.
Early blueberry (Vaccinium ovalifolium) is one of the first flowers that appear in spring, usually when ruby-throated hummingbirds first arrive in spring.
Salmonberry started putting out its first spring leaves last week.
Fiddleheads are an important local food in coastal forests. These are the most common species, called lady's fern (Athyrium felix-femina)

Sunday, April 8, 2012

Apples and Cherries in Bloom

Japanese crabapple (Malus floribunda) turns our street pink in color this time of year

What a lovely time of year! It is still early here at the edge of the Great Plains. Native prairies are still mostly brown but in town the streets are covered with the snowy blossoms of cherries, apples, & pears, and bright pink or red flowers of Japanese crabapples. Many people have asked me how you tell the difference between these closely related trees, and I know others are sometimes confused by them so here are a few hints.

All these fruit trees are in the Rose family so look quite similar since they are so closely related. You might say the easiest distinction is that cherries produce cherries and apples produce apples. But of course that does not help very much when we are looking a flowers in the spring!

In general the apples have larger more robust flowers and the cherries are smaller and more delicate. But to really tell them apart you need to pick a flower and look carefully at it. The key is in looking at the female parts in the center of the flower. Cherries and their relatives just have one female part the pistil with one thick stem-like style. Apples on the other hand have multiple styles. If you want to get even more technical you can cut the flower in half and look for where the base of the pistil (the ovaries) are located. If they are located below the base of the flower (inferior) they are apples, if they are located right at the base of the flower (superior) they are cherries.

There are a bewildering array of ornamental and agricultural varieties of cherries and their close relatives including apricots, plums, peaches, and almonds. All have stones or pits in the center of their fruits, often poisonous, which seems like a good way to lessen the chance that animals will not destroy the seeds within, and make them good seed dispersers!

Most of our popular fruits from this family come from Europe, the Middle East or Asia. They all seem to readily cross pollinate each other leading to many hybrids and many varieties. This is also why they have been such an important source of food for people for so many generations. You can produce just about any texture or flavor or color of fruit from these trees. It just takes patience.

For the Project BudBurst Cherry Blossom Blitz, seven distinctive species are highlighted. If you find a tree that does not seem to fit the descriptions and following some of the hints above it is still clearly a cherry then you can list it as "other cherry".

In northern Colorado its been a wonderful year for the blooms of these trees. Warm temperatures, and no heavy frosts led to flowers coming out about 3 weeks early this year. Apple flowers first emerged on April 2nd, and are slowly coming into full bloom. Most of the crabapples are in full bloom today, first with the tough Siberian crabapples with white blooms, and now with the pink Japanese crabapples. Sweet cherries are in full bloom now, but pie cherries are still in bud, and chokecherries are just starting. So there is a bit of a pattern with timing of the flowers of these trees, but in this early spring you can sometimes see many of them in bloom at the same time. Looking at and photographing these exuberant flowers is a wonderful way to enjoy a warm spring day!

Paul Alaback

Tuesday, April 3, 2012

What a warm March we have had!

Crabapples put on a spectacular display almost a month early in Berthoud, Colorado

Today there are a lot of articles in newspapers and on the web about what an exceptionally warm March we have had all across the country. This past March has been a great opportunity to learn how adaptable our plants are to changes in weather. Here in northern Colorado the average daily temperature in March is normally 50 degrees F, but this year it actually averaged 58.6, and there were many days with high temperatures in the 80's! What was remarkable about this past March was it was so warm not only here in the Rockies but all across the country. We have been getting all kinds of reports to Project BudBurst especially from the midwest and east, of flowers appearing a month or more early this year. Climatologists say that such an unusual warm spring has not occurred like this since 1910, so it is an exceptional year indeed. In a northern climate to have flowers appearing a month early is pretty amazing. That is a huge change in the growing season!

Here in Colorado our warm March has resulted in some of the earliest records of flowering since Project BudBurst started 5 years ago. Just looking at where I make observations on a 1 mile loop around my town it has been quite an amazing pattern to see. Most plants that I have records for have flowers that appeared 15-28 days early this spring. This is consistent with some studies of how plants respond to changes in temperature. A particularly detailed study from Europe from the 1800's to the present showed that plants should put out flowers about 4 days early for every 1 degree C increase in temperature. For my area near Loveland, CO this comes out to about 19 days earlier, or right about the average for the plants I have been observing here (my average is 20.4 days).

Like many other topics in science you learn as much from the exceptions as the general rule. Here the exceptions to this rule, at least this year, are Quaking aspen which is only 7 days early, dandelions only 5 days early, and silver maple which flowered at exactly the same day last year and this year. Why? No clear answers yet but Project BudBurst data from here and places all over the country should provide scientists with lots of clues and puzzles to work on!

Paul Alaback