Friday, July 8, 2016

What did Spring Look Like for Harvard Forest Ecologists?

Two Harvard Forest Scientists share with us what spring looked like through the lense of their data.

From Ecologist Joshua Rapp:  

Joshua Rapp is a plant ecologist interested in how life history influences the interactions of plants with their environments, and ecosystem processes.  He is currently a Bullard Fellow at Harvard Forest, and will serve as the project Ecologist for the Our Changing Forests project Summer Institute for Teachers on August 25th.  

Maple Syrup Season

From the maple tapper’s perspective it was an early spring. You can see a graph comparing the past few years at HF and my comments on the maple sugaring season here:

Some excerpts from Joshua's website related to the maple syrup research give a summary of what Spring looked like in the world of Maple Syrup.  

I tapped the trees on February 1, the earliest I’ve tapped by more than 2 weeks, and collected sap throughout the first week of February.

March 30, 2016. The tapping season is officially over – cold nights and warm days of late have not resulted in dripping taps. This is not because the sap isn’t flowing in the trees; instead, the taps have become clogged with bacteria, which also clouds the little sap that does manage to drip from the taps. A warm spell 3 weeks ago caused the end of big flows, although sap continued to dribble out for a while, at least in the sugar maples. Overall, the early season was good for sap flow -second largest in the past 5 years, but only an average year for syrup since the sugar content of the sap was on the low side – second lowest in the past 5 years. I collected sap 25 times, the most I’ve done in a year. Most of the sap flows were low to moderate, but a few were quite high, including the 2 biggest one-day flows I’ve seen.

Maple and Oak Flowering: 

Joshua Rapp's research is looking to see connections between maple tree's production of sugar and masting.  Masting is a term that means synchronous production of seeds over large geographic areas. Think acorns or samaras.  Flowering is the precursor of fruit production so that is looked as as well.  It is thought that there is a tradeoff in energy the tree spends on sugar production vs. flower and seed production but it is not well studied. 

Re: Flowering this spring:  It was a slightly early and low-moderate flowering year for sugar maple. In the attached figure (below), a couple of sugar maples on the right side of the road are flowering, but the ones on the left side are not.

From what I observed, it was a very high flowering year for red oak, and the trees had many small 2nd year acorns. Red oaks take two years to mature acorns, so last year’s pollinated female flowers are small acorns this spring and will be full size by fall. This year’s fertilized ovules will become mature acorns next fall. It will be interesting to see if this results in two red oak mast years in a row (this year and next). 
Canopy View of Oak Flowering at Harvard Forest by Joshua Rapp

To see more about Joshua Rapp's Masting and Maple Syrup research go to his website at: 

 To see recent articles and radio stories about Joshua's research this winter and spring, see:  

 The Post-TribuneChicago Tonight, and Indiana Public Radio each did articles about Josh's newest sample site at the Indiana Dunes National Lakeshore. 

The Worcester Telegram ran a story. Climate Central also published a piece. Also see:  MassLiveWWLP-22News, the Westfield News and The Recorder

To see more about the Our Changing Forests Schoolyard Ecology project, go to:

To begin the Our Changing Forests Schoolyard Ecology project for students in grades 7-12, see the flyer and registration form at:


From Buds, Leaves and Global Warming Project Ecologist, John O'Keefe: 

John O'Keefe has been studying tree phenology at Harvard Forest for 26 years.  He monitors when leaves emerge in the spring (bud break) and when the leaves drop in the fall (leaf fall) in order to determine whether the growing season is getting longer as a result of global climate change.  In summarizing his spring 2016  tree phenology research, John O'Keefe  had this to say: 

I  just finished entering this spring’s data and calculating the bud break dates.  As I suspected, despite the record warm winter and early spring, the cool, cloudy April really slowed things down and we wound up with quite a late spring.  Once the leaves emerged the weather warmed up and they developed fairly rapidly, so the 75% leaf development date wasn’t especially late.  This points out that it is really the weather during April and early May that determines when leaf emergence will occur.  

See graphs below from John O'Keefe: 

 Note that 2016 was one of the 5 latest 50 percent Budburst date from this 26 year study.  

Note that this graph shows the mean 75%  leaf development over 26 years.  This year seems to be later than average but not among the top 5 latest as was bud break.  

This is a complex figure showing the Mean 50%  budbreak, 75% leaf development and 50% leaf fall for 4 tree species all on one graph.  

Notes to help interpret the key:   Species ACRUBB stands for Acer Rubrum (Red Maple) bud break.  The BEALBB is a birch species bud break. QURUBB is Red Oak, QUALBB is White oak budbreak...ACRU 75 is the 75%Leaf development for Red Maple,  etc.  The ACRUL50 depicts the leaf drop date for Red Maple, and so on.    

It is helpful to see the overall trends all together here to see overall patterns.  The bottom set of lines shows Spring data over time while the top set of lines shows the fall data over time.  

To see more about John O'Keefe's own long term research go to:

To see more about the Buds, Leaves and Global Warming Schoolyard Ecology project for students in grades 4-12, go to:

To begin the the Buds, Leaves and Global Warming study, see our flyer and registration form for the Summer Institute for Teachers at:


Friday, July 1, 2016

Pictures of Spring in Photos and Data

The Data is In; What did Spring Looking Like this Year?

On Friday we went up to the pool for the last time this year. We also returned some of the critters we had been keeping in the classroom. I also just uploaded all the data for this spring.

Judy Gibson, Francis Parker Charter School, Devens, Ma. 



Field Site Photos can be shared in Field Site Description section of the online database.

Teachers can email their field site photos to Emery Boose to post on the online database at any time.
Excerpt from HF Schoolyard  Field Site Data Base with link to Photo Above

Schoolyard teacher, Janet Gordon has sent this photo of her field site from Tewksbury High School.  See all sites' field site data at:

Views from New York City


Photos and Excerpts from Brooklyn Technical High School students led by teacher Elisa Margarita.  In her first year with the Schoolyard Ecology program, Elisa collaborated with veteran Schoolyard Teacher, Lise Letellier from Holyoke, Ma. to engage her students in analyzing and interpreting data.  

Mei Hua Mei's AP Environmental Science Harvard Forest Schoolyard LTER program Report. 

The question of global warming and climate change is the theme of this experiment and the effect of both may be demonstrated through this intensive research conducted by Harvard's long term ecological research. Although  the data presented above is only a small portion of the large platter of information presented to Harvard yearly, my data and the data collected this year is contributing to a larger look at the effects of climate change and global warming on our ecosystems. Climate change is creeping up on us, and we do not even realize it. Throughout the years, our ecosystems have been slowly changing and we may not have noticed because of these slow changes. With year after year of contributions to the study, Harvard is able to piece together a broad spectrum of the effects of Climate change; effects that may not to obvious to us in our day to day lives. 

Wrapping Up:
Through this experience, I was able to learn about collecting data and conducting research. It felt really great to be apart of a study that has been running for so long. It was truly an honor to be able to say “I am doing a project for Harvard.” Since this project started in the beginning of APES class, it was a good introduction to the skills we would need for the rest of the year. For example, we learned how to collect data, take measurements, identify trees, make observations, handle tools, work as a group, and more. So, not only was the Harvard Lab an honor to conduct, it was also a vital introductory project that would lead us to the rest of the course with an understanding for conducting research and working as scientists in a group. 
This project was very eye opening and interesting to conduct. However the class and I encountered some difficulties. Since we did not have(past) data for our trees, we had to use data from another school. This presented a loss of purpose for the assignment because a large portion of our report went to analysing information for a tree we did not observe. This problem can be easily fixed by entering the data for our trees onto the Harvard database. 
My favorite part of this project was having an opening and closing for our APES year. The Harvard Project was our opening assignment for the school year and one of the last assignments in the closing of the year. We started this project with all of our Firsts of the year. Our first time going to fort greene for class, our first time doing a lab, and our first time working in groups with kids that we barely knew. And by the end of the year, when we went out again to take our Spring data, it was our two hundredth time going to fort greene for class, our nine hundredth lab, and our fiftieth time working in groups with our closest schools friends.

Mohamad Amin                                                                                                                6/12/2016
AP Environmental Science

Harvard Forest Schoolyard Ecology - American Elm and Red Maple

            Our tree was an American Elm, or Ulmus Americana, it is a deciduous tree with a range all across the eastern United States, it favours a whole range of habitats but generally likes being near areas with lots of water. It is a highly resistant tree, the common enemy of this tree is the Dutch elm disease. It has elliptic to lanceolate leaves that are pinnate and serrated, the leaves are arranged alternately. This tree has a long growing season and can continue growing into the late fall, unaffected by the loss of sunlight.
            This experiment was a group project, as a group we were free to select a tree and we chose the American elm. During the autumn we measured the rate at which the leaves of the tree changed colour and when/if the trees finally separated from the branch. This was a weekly task and continued until winter. Once winter was over and spring began, the project restarted with a different focus; we were to measure the buds of the tree and see how long it took to begin sprouting new leaves.

            Due to complications involving our data, I was not able to complete this project using my own data. Instead I had to use data from the Harvard Tree database. As of such I chose a Red Maple from the data taken by Holyoke Catholic High School. The Red Maple is another extremely hardy species with a varied habitat.
The data taken from Holyoke indicated that this tree quickly bursts and gets it leaves during the end of April and beginning of May. The Red Maple would go from no leaves at all during the week of April 20th, it would have seventy percent budburst during the following week and by the tenth of May it would be fully opened.

 Leaf Length follows similar trends to the budburst. The tree is completely devoid of leaves until the end of April but once the buds have burst, the  leaves grow rapidly. They reach 2 centimeters by the end of April and quickly jump up to the 10 centimeters by around the beginning of May. After it has reached ten centimeters, it quickly flattens out and stops growing. This is indicative of quick growth and it would mean that Red Maples can quickly establish themselves.

Trends can also be seen with the changing of leaf colours for the Red Maple. The Red Maple seems to have a slight on or off switch with the colour change. For the majority of the year, since it gains its leaves they maintain a solid 2.0 tree color. However during the week of 23 October, the tree undergoes a radical shift and the leaf colour shifts radically. It gains its famous red coloration and is part of the standard colour changing during the autumn season. The colour changes rapidly from green to red, once the change begins and completes itself within the week, the colouration does not change much anymore.

The amount of leaves that have fallen from the trees followed similar trends too. The tree would be completely fine for most of the year until a week in October. The week of October 29th saw the Red Maple completely lose all of its leaves. It was not even a period of a week, it was closer to four or five days, but in that time the Red Maple managed to go from 0% leaf lost to 100% leaves lost. During this time, Data was only taken twice between the time it went from 0 to 100 percent lost. At one point it was at 40 percent but by the next time of data collection, all of the leaves had fallen.

This project was a complicated a long term one. The American Elm tree that we originally selected was a major part of it, we got a lot of data on it but the fact that it was not very organized (the Spring data was submitted and we didn’t have a backup) meant that it could not actually be used for this report.

Spring Budburst Data Looks Like this from across 4 Schools: 

Westfield, Mass.  

Easthampton Mass.

 Holyoke Mass.

Worcester, Mass. 

Explore more data from this year

To see all data entered to our database this year go to:

download Schoolyard data

To see sites and their data on our interactive site map go to: 

Interactive site-data map

To graph data from any of our Schoolyard field sites, go to:

Online graphing tool

Stay Tuned for part 2 of Looking at What Spring Data Looks Like..from Harvard Forest Ecologists and Schoolyard resources..Coming Soon