# The Use of Muld and Shading Improves the Survival of
## 3 Results  
At the planting date, the means per species for diameter ranged from 3.1 mm to 4.8 mm and for height from 15.1 cm to 27.1 cm (Table 1). The preliminary analysis of variance on initial dimensions showed only a main effect of species D and H (Table 1, \(p<0.0001\)). _C. alba_ and _A. cavern_ had the highest D and H, respectively. Initial dimensions were more heterogeneous for H than D, with _A. cavern_ and C. alba_ being the species with higher (38.1%) and lower (20.8%) coefficients of variation, respectively.  
\begin{table}
\begin{tabular}{l l l l l l} \hline \hline  & \multirow{2}{*}{**N**} & **D** & \multicolumn{3}{c}{**H**} \\ \cline{3-5}  & & **Mean (mm)** & **CV (\%)** & **Mean (cm)** & **CV (\%)** \\ \hline Ca & 54 & 4.8 a & 18.2 & 15.1 d & 20.8 \\ Mb & 108 & 3.1 c & 20.8 & 23.1 b & 25.4 \\ Qs & 108 & 3.9 b & 16.3 & 19.5 c & 23.7 \\ Ac & 162 & 3.2 c & 18.1 & 27.1 a & 38.1 \\ Sp & 54 & 3.8 b & 13.1 & 23.6 ab & 32.5 \\ \hline January & 162 & 3.4 a & 24.8 & 24.2 a & 42.6 \\ April & 162 & 3.6 a & 25.7 & 21.2 a & 30.8 \\ June & 162 & 3.6 a & 21.5 & 22.8 a & 32.5 \\ \hline ANOVA & & & & & \\ Date (PD) & & 0.1501 & & 0.2823 & \\ Species (Sp) & & \textless{}0.0001 & & \textless{}0.0001 & \\ \(\text{PD}\times\text{Sp}\) & & 0.4881 & & 0.2538 & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Number of trees, mean and coefficient of variation (CV) for initial diameter (D) and height (H) at the planting date per specie. Ca: _C. alba_, Mb: _M. bazia_, Qs: _Q. saponaria_, Ac: _A. cavern_, Sp: _S. polygamous. p_-Values are from the analysis of variance on D and H. Different letters indicate significant differences according to [PERSON]’s test.  
There was high plant mortality at the island plot level; 56% of the island plots did not present any surviving seedlings, and only 15% overcame a survival level of over 50%. None of the interactions tested were significant for survival (\(p>0.05\)) (Table 2). However, we found a significant main effect for all the factors in this trait (Table 2). Survival was increased around fourfold when (1) planted in June relative to the other months (Figure 2A), (2) applying mulch (Figure 2B), and (3) shading seedlings with either level (T35 or T70) (Figure 2C).  
On the other hand, the island plots planted in June, with mulch and shading, averaged 82% survival. We found significant differences in survival among species (\(p=0.0005\)), which were mainly explained by the high survival in _S. polygamous_ (27%) relative to _C. alba_ (7%), with the other species having intermediate values (Figure 3). One year after outplanting, there were significant differences among species for increments in diameter and height, but these traits were not affected by the other experimental factors (Table 2, Figure 4). _S. polygamous_ had the highest survival but also the highest growth increments, whereas the lowest growth increments were observed in _Q. saponaria_.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Source of Variation** & **Surv** & **IncD** & **IncH** \\ \hline Date & **0.0003** & 0.2515 & 0.3763 \\ Mulch & **\textless{}0.0001** & 0.1734 & 0.1329 \\ Light & **0.0003** & 0.8712 & 0.5673 \\ Date \(\times\) mulch & 0.3106 & 0.8906 & 0.6049 \\ Date \(\times\) light & 0.3012 & 0.4164 & 0.5966 \\ Mulch \(\times\) light & 0.4402 & 0.56037 & 0.9335 \\ Date \(\times\) mulch \(\times\) light & 0.9991 & 0.9989 & 0.9986 \\ Species & & **0.0085** & **0.0123** \\ \hline \hline \end{tabular}
\end{table}
Table 2: \(p\)-Values from the analyses of variance for survival (Surv), increments in Height (IncH) and diameter (IncD). Significant values at 0.05 are shown in bold type.  
Figure 2: Mean survival per planting month (**A**), mul application (**B**), and shading level (**C**). 0 Mulch: no mulch application; 1 Mulch: mulch application. T0: full sun, T35: shade at 35%, T70: shade at 70%. Different letters indicate significant differences according to [PERSON]’s test.