1 2Black spruce-lichen woodlands are low tree density stands within the 3 closed crown, North American boreal forest that represent a diverging post-fire 4 type of black spruce forest. As natural densification of lichen woodlands has 5 never been observed, plantation remains the only way of shifting these stands to 6 closed canopy stands. The objective of the study was to evaluate site preparation 7 effects on growth and water relations of black spruce (Picea mariana (Mill.) 8 B.S.P.) and jack pine (Pinus banksiana Lamb.) seedlings in black spruce-lichen 9 woodlands (LW), compared to managed black spruce-feathermoss stands 10 (BSFM). Site preparation treatments in LW were no preparation (LWno), patch 11 scarification (LWps), and disk scarification (LWds). The operationally managed 12 BSFM stands stood for the control. Results from the third growing season 13 indicate that soil water availability in intact or lightly prepared patch scarified LW 14 is a limiting variable for seedling growth for both black spruce and jack pine 15 seedlings. However, once LW are prepared with disk scarification, this planting 16 check factor is significantly reduced, to the point of being equal to BSFM in terms 17 of water availability and seedling water relations. The significant seedling growth 18 difference, in favor of BSFM, might be a consequence of the lower level of pre-19 plantation disturbance in LW, compared to BSFM. Our results also suggest that 20 jack pine, through higher water stress tolerance, could constitute a wise 21 silvicultural choice over black spruce, especially with LW established on coarse 22 drought-prone material. 23 3 1

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Remote sensing techniques of measuring red and far-red crop canopy reflectance are frequently used to estimate crop canopy characteristics. The variability introduced in reflectance data from nonvegetative factors such as wind decreases the usefulness of the techniques. The objective of this study was to quantify and minimize the variability kom wind on spectral reflectances. Red and far-red reflectances were acquired above wheat, barley, and affalfa canopies throughout days of changing wind conditions. Periods of 312 s with little changes in irradiance values were used for the analysis. Wind had negligible effect on reflectances of a short canopy such as cut affalta, while it had a significant effect on reflectances from canopies with a higher vertical structure, partiodarly during gusty conditions. Within the windy and calm periods, extreme values of spectral reflectance differed by 60% and 12%, respectively, in the red, and by 40% and 8% in the far-rod for the barley canopy, For the compact and dense canopy structure of altaffa, these differences reached a maximum of 10% under windy conditions in both spectral regions. The plant canopy architecture, the wind conditions, and the spectral regions all affected the magnitude of the influence of wind on crop canopy spectral reflectances. The mean reflectance of a canopy overestimated the true reflectance by 2-4% while the use of the median reduced this overestimation. Sampling requirements for this sensor are evaluated, and the possibility of decreasing either the sampling rate or the sampling period is discussed.