In 1978 the company started to plant pine forests, and in 1999 the first sawmill was built to add
value to the plantations. Rapid industrial growth generated a high demand for wood, which
required an increase in the rate of planting, advancing on livestock land and reducing the
number of dams. We found a good solution to this in silvopastoral systems, which integrate
trees and grazing livestock operations on the same land. At present, silvopastoral systems are
used for the management of half of the company’s forested land.
We consider SPSs to be a productive model that should be designed and managed as a third
option to traditional livestock and forestry.
In the company we have the entire production chain: from the seed orchard where we
harvest the seeds of hybrid pine (Pinus elliottii x Pinus caribara var. Hondurensis) to the nursery
for the production of seedlings that are then planted, handled, harvested and finally
industrialized in the sawmill and
remanufacturing plant mostly for the
production of moldings for export.
Our entire production is FSC certified.
The current silvopastoral model has a rotation
of 16 to 18 years; the planting is laid out in
double rows separated by 4 meters with 12
meter alleys. The initial density is 500 plants/ha;
after a commercial thinning in the tenth year,
the cycle ends at 200 trees/ha. The final
objective is to obtain few high-value trees for their better industrial performance.
The management of densities and pruning favors the entry of light, which is necessary for
grass to grow. Managing this balance is a challenge: every detail has to be planned and there
have to be clear goals.
Wood yield at the end of the growing season ranges from 160 to 180 t/ha. Pruning is carried out
to eliminate basal branches in juvenile stages with the aim of obtaining knot free wood (clear)
in logs with 36 to 40 cm diameter at breast height (DBH). This product has the highest value in
the wood market. Compared to traditional forest management with high densities, we
produce 70-75% of the wood volume of those systems.
Silvopastoral Systems (SPS) constitute a productive model where meat and wood are
produced on the same land surface, being the sum of both activities of greater economic
return than doing them separately.
An increasingly valued advantage is the
reduced risk of losing plantations to forest fires.
Trees separated, pruned and with grazed
pastures are at lower risks than forest stands.
SPSs require strict light management under the
tree canopy; delaying thinning has a negative
effect on tree growth and an even greater
impact on forage production due to the lack of
light. We carry out SPSs on natural fields, planted
pastures (Brachiaria brizantha, Brachiaria
humidicola and Setaria sp.) and winter annual
grasses (Lolium multiflorum). Water content and
microbial activity in SPS soils is higher than in
open plots. In winters, the effect of frost on
pastures is lessened, reducing the winter gap.
There are a number of benefits for livestock from the point of view of animal welfare. It is well
known that animals prefer to ruminate in cool places, protected from the sun. Trees spread
throughout the pasture allow for a better distribution of feces (in the open, the highest
concentration occurs in forest areas or near watering places) and less movement of cattle in
search of shade. As a prey animal, the cow is more protected under forests than grazing in the
open. The environment achieved under SPSs is ideal for the most delicate categories of
livestock, such as replacement heifers or first calving cows. We have had no problems
managing calving in these environments.
From the environmental point of view, carbon sequestration by trees, without displacing
livestock practice, generates additionality” to the system. Our measurements since 2017 show
that the company's livestock is carbon neutral beef. Each forested hectare sequesters an
amount of carbon dioxide equivalent to the emission of methane by 6 to 8 bovine animals.
Most of Zeni’s industrial products retain carbon for more than 30 years.
Producing under controlled costs is the concept we apply to SPSs, where the main limitation is
working capital. Most silvopastoral systems are being developed by family livestock
enterprises that see trees as a way to increase their assets while continuing to produce meat.
The change that occurs when plantations begin to be cut is significant, modifying the size of
the company. It is an excellent option to incorporate family partners to the livestock fields,
making the forestry investment without displacing the livestock practice and generating
future resources for the company and the family investor as well.