diff --git a/src/phenology/budburst.jl b/src/phenology/budburst.jl
index d17d2f0..eff5e57 100644
--- a/src/phenology/budburst.jl
+++ b/src/phenology/budburst.jl
@@ -24,8 +24,8 @@
     =========#
 
     # Budburst only when forcing requirement met. No budburst when coppiced i.e. WS == 0.
-    budburst(F, Rf, bud_max, WF, coppiced) => begin
-        (F >= Rf) && (bud_max >= WF) && !coppiced
+    budburst(F, Rf, bud_max, WF) => begin
+        (F >= Rf) && (bud_max >= WF)
     end ~ flag
 
     # Degree units for budburst. Actual
diff --git a/src/phenology/dormancy.jl b/src/phenology/dormancy.jl
index b45a318..bbd5d55 100644
--- a/src/phenology/dormancy.jl
+++ b/src/phenology/dormancy.jl
@@ -15,6 +15,7 @@
 
     DD(T_air, T_dorm): dormant_degrees => (T_air - T_dorm) ~ track(when=dormant, u"K")
 
+    # incorporate effect of day length for chilling requirement
     dC(DD) ~ track(max = 0, u"K")
     C(dC):  chilling_accumulated ~ accumulate(when=!chilled, reset=senescent, u"K*hr")
 
diff --git a/src/phenology/shooting.jl b/src/phenology/shooting.jl
index 883eb88..52edf6f 100644
--- a/src/phenology/shooting.jl
+++ b/src/phenology/shooting.jl
@@ -9,7 +9,6 @@
     shoot_max => 1e4 ~ preserve(parameter, u"kg/ha")
 
     shooting(F, Rf, shoot_max, shoot, WS) => begin
-        # false
         (F >= Rf) && (shoot_max >= shoot) && (WS <= shoot_max) 
     end ~ flag
 
diff --git a/src/physiology/mortality.jl b/src/physiology/mortality.jl
index 83b70c9..cb29337 100644
--- a/src/physiology/mortality.jl
+++ b/src/physiology/mortality.jl
@@ -71,7 +71,7 @@ This system calculate age and stress related mortality.
     # Follows the "self-thinning" rule.
     "Self-thinning rate"
     selfThinning(accuracy, mS, stemNo, WS, wSx1000, thinPower) => begin
-        n = stemNo / 1000u"ha^-1"
+        n = stemNo / 1000u"ha^-1" # Trees density ?
         x1 = mS * WS / stemNo
         i = 0
         while true
@@ -92,5 +92,5 @@ This system calculate age and stress related mortality.
     Mortality
     ========#
     "Tree mortality rate"
-    mortality(asMortality, selfThinning) => asMortality + selfThinning ~ track(u"ha^-1/hr", when=flagMortal)
+    mortality(asMortality, selfThinning) => asMortality + selfThinning ~ track(u"ha^-1/hr")
 end
\ No newline at end of file