The day starts out early. My assistant, Juan, and I are in the car driving towards Rincon de la Vieja a little after 6 am. We arrive at Hacienda Lodge Guachipelin and greet the owner, Don Tomas. He sets us up in the restaurant to talk about the land. I have worked with many landowners here in Guanacaste—I’ve had farm limits sketched for me with sticks in dusty patches of earth—but Don Tomas pulls up google earth and shows us the forest, rivers, roads, and points out the property limits.
Juan and I hop back in the car and head towards a patch of oak forest. Juan and I will delineate a forest plot that is 50 by 20 m. Within the plot, we will measure and identify all tree species with a girth of 5 cm or above at 1.3 m height. I have been working in farms all around Guanacaste for the past 7 months and the data from this plot will be added to the dataset I am building of private forests in Guanacaste. I will use this dataset to assess tree biodiversity and carbon stocks on private farms within Guanacaste. Within the plot, we will also collect soil samples to assess soil chemical and physical properties. For the carbon stocks, I will use species-specific wood density measurements to estimate the carbon stored in trees. Costa Rica has done a superb job of protecting forests—25% of Costa Rican land is officially protected. Yet the majority of forests (~76%) are on private lands. Therefore, understanding carbon stocks in private forest are important for helping Costa Rica reach its goal of becoming the first carbon neutral nation by 2021.
The first plot we set up on Hacienda Lodge Guachipelin property is young secondary forests of between 10—15 years. The plot is dense with young trees and Juan and I maneuver through the stand and place the flags to outline the plot. Juan gets started collecting the soils and I measure tree girth and identify species. The plot is within an oak (Quercus oleoides) dominated forest; interestingly, Guanacaste is the Sothern limit of the oak genus.
Also in the plot are the ubiquitous bullhorn acacia (Acacia cornigera). Bullhorned acacia have a remarkable symbiotic relationship with ants; the plant provides a place for the ants to live (hallow thorns) and food to eat (glands that produce sugars). The ants, in return, provide fierce protection. If you have ever bumped up against a bullhorned acacia, you’ll know instantly the fiery sting of that protection. On a bullhorned acacia in the plot I notice a beetle who has impaled himself on the needle end of a thorn. The ants are furious and swarming and the poor beetle is flailing. I feel like I am watching an action packed sequence on the Discovery Channel.
Once we complete the plot, we drive to another part of the property and find some oak forest that is about 20-25 years. This plot is much more pleasant to work in—the canopy is dense, are birds singing above us as we work, and there are lovely purple-flowered vines in bloom.
This plot is also an oak-dominated forest but there are a few species that I haven’t come across yet in Guanacaste. Although I’ve been avidly studying the tree species, there are still plenty that I am not familiar with. When I come across a tree species that I don’t know, I do one of two things: (1) collect leaf samples for later identification or (2) tag the tree with biodegradable flagging and return with a botanical expert. Today I am tagging, so I slip blue tagging tape around the tree. The next tree I measure is one of my favorites, perhaps because I learned it early on so it feels like an old acquaintance Madroño (Calycophyllum candidissimum). The genus name, Calycophyllum, is fitting because the tree bark is the color of a calico cat.
Juan and I finish up the plot and head out of the forest. This has been a great day. We head down the road as the sun turns top of the forest orange.