Despite the technological evolution on the forest tree seedlings production, there are
several problems to be solved yet. Seedlings out of pre-established morphological
standard and/or older than the age recommended for planting, seedlings grown in
unsuitable containers are some of the problems which can result in unsatisfactory
results on the field. This paper aimed to evaluate the effects of seedlings age, the
effect of containers type and the planters team effects on the Pinus taeda trees
growth and root system morphological architecture 46 months after their planting.
Eight treatments were planted in a randomized block design distributed on a factorial
design, with two planters team: 1. specially trained; 2. ordinary, and four seedling
production methods: 1. plastic tubes of 55 cm3 (six months of age); 2. plastic tubes of
55 cm3 (ten months of age); 3. plastic tubes of 126 cm3 (six months of age); 4. bare
root seedlings (nine months of age). The field trial was established on four blocks,
with eight treats and 25 plants per plot. Treatments were randomized within blocks
and data were collected only on the nine inner plants in each plot. A row of trees out
of the blocks was planted as external border. Seedlings height was evaluated just
after planted. Plot volume (survival, height, DBH-diameter at breast height), small
root weight and root system architecture were evaluated at 46 months of age. A
cylindrical sampler was used to collect small roots and a big tractor with special
equipment used for digging was used to remove the whole root system. Architecture
of each root system was classified based on the photograph analysis taken at three
angles (front, side and from the top). When necessary, the data were transformed to
attend the requirements of the analysis of variance (ANOVA) and analysis of
covariance (ANCOVA). Spearman correlation was used to evaluate relations
between traits. Based on the results observed, it was conclude that: the seedling
production method affect the tree height and DBH growth (and volume per plot), but
do not affect the small roots weight and the architecture of the root system of 46
months P. taeda trees; the method of production M3 (containers of 126 cm3,
seedlings with 6 months of age) is better in terms of growth; trees originated from
seedlings with six and ten months of age, grown in 55 cm3 containers, shown similar
height and DBH at 46 months of age, but also shown different survival, which affect
the total volume per plot; trees originated from six months of age seedlings grown in
126 cm3 containers shown better DBH and height growth, but similar volume per plot
when compared with trees originated from same age seedlings grown in 55 cm3
containers; The training provided to teams of growers improves survival rate,
therefore, the volume per plot. However, it should be emphasized that the excess of
trampling can affect the development of the architecture of the root system of trees of
P. taeda;DBH is highly correlated with individual tree volume and the mean DBH is
medium correlated with mean plot volume at 46 months of age; the root system
architecture of 46 months P. taeda trees can be evaluated by mean of excavation,
with moderate accuracy, attributing it note to the view of top, without necessity
removal the tree, reducing cost and time.
