Cloud Forest

From May 16-20 of this year, the seventh grade teachers moved their classrooms to the mountain village of Jalcolmulco in the eastern state of Veracruz. For science this meant lessons taught in a piece of remaining cloud forest in the Francisco Javier Clavijero Botanic Garden in nearby Jalapa. Entering the cool, shaded ecosystem, one's attention is immediately grabbed by the change in temperature and the smells of moist earth and rotting leaves. It was the perfect place to take our plot studies outdoors and practice what the students had learned at school.

Just as they had done in our land laboratory in Mexico City, students recorded measurements and made observations about the abiotic environment: map coordinates, elevation, soil temperature, air temperature at surface and waist levels, soil texture, amount of sunlight. Focusing on square meter plots, students made an inventory of plants and drew representative examples of what they saw. It was inspiring to work

in such a healthy habitat and students took the task seriously.

Here are some of the data that were recorded on May 17 between 9:30 and 11:30 am:

Latitude: 19 degrees, 30.755' N

Longitude: 96 degrees, 66.603' W

Elevation: 1,324 m

Temperatures

Soil: 20 degrees C

Air at soil surface: 21 degrees C

Air at waist level: 20 degrees C

Cloud Cover

It was completely overcast and as the morning adv

anced, a light rain developed.

Such data is rather typical of cloud forests which are found in the mountains at tropical latitudes. In this case we were in the Sierra Madre Oriental in the watershed that feeds rivers which empty into the Gulf of Mexico. The abundant moisture creates a favorable habitat for a number of plants with sunlight being the main limiting factor. As a result, cloud forests are home to an array of epiphytic plants, that is plants that grow on plants to reach for light.

Monarch Flyover

Yesterday, while working in our country garden, we were rewarded with an inspiring sight. Riding the gusting southerly winds on fragile wings, dozens of monarch butterflies were on their way back to the US and Canada. For over an hour the exodus continued, twos and threes and tens. Some flew high, just specks in the sky. Others skimmed the treetops of our cedar hedge. A few slackers dipped down for a pull of nectar from our calendula flowers. Relentlessly they kept their course, plotted by their tiny insect on-board computers, following magnetic fields North.

Their departure was a bit late this year. It has been an unusually chilly March, Cold Front #34 just having blown through last week. Happily, it was one of the larger flights we have seen in recent years. Newspaper had reported a 30% increase in the population this year, but I wonder about those figures, given the acreage of fir trees that has been cut in the nearby forests of Michoacan. And just how were those population estimates made? Still, it was encouraging to see so many and hope, for a moment, that this unlikely migration might continue into the future.

Student Work

One of the pleasures of teaching is to introduce students to the natural world and ask them to observe and draw what they see. For many children this is difficult, in part because of limited artistic skills, but also because they are still developing their ability to "see." Above are examples of two young people who "see" very well. Natalia (on the left) went deep into the Lantana camara flower to notice that it is actually composed of many tiny flowers clustered together. Naomi (on the right) noticed that the leaf of the Tecoma stans is actually divided into many smaller leaflets.

Having a land laboratory on campus allows us to observe nature without ever leaving the school grounds. Students are given instruction sheets and then, together with their team members, they study a particular area within the garden. At this point in the year, the garden is beginning to come to life, as evidenced by the blooming flowers. This rebirth was an inspiration for these young ladies to capture these treasures of Spring.

Plot Study in the Humboldt Garden

During the Ecology Unit in the winter semester, students visit the Humboldt Garden to have firsthand contact with an ecosystem. Working in teams, students record information about abiotic and biotic factors within their plot. Later in the classroom, students will share their data with others and look for patterns.

Measurement is a necessary first step in being able to detect those patterns. It is fitting that the activity takes place in the Humboldt Garden since precise documentation was central to his method. During their exploration of South America and Mexico he and his partner, Aime Bonpland, carried with them a virtual traveling laboratory with more than 30 state-of-the-art instruments to measure the physcial environment. In collecting this data the Prussian explorer hoped to better understand the "unity of nature."

The measurements we take are just a beginning. Students measure soil temperature and air temperature at the surface and at waist level. For many it will be the first time that they pay careful attention to the scale within a thermometer. This skill will be useful to them as they continue their work in science in later grades. Back in the classroom the children will make a comparison table of temperatures at different levels in different plots. When the sun begins to strike the garde, there can be large temperature differences in a small area. This simple exercise gives the student an understanding of how differences in exposure can generate different micro climates.