diff --git a/src/libslic3r/Support/TreeSupport.cpp b/src/libslic3r/Support/TreeSupport.cpp
index a1e983cb67..9b199adc45 100644
--- a/src/libslic3r/Support/TreeSupport.cpp
+++ b/src/libslic3r/Support/TreeSupport.cpp
@@ -2011,7 +2011,7 @@ void TreeSupport::draw_circles(const std::vector<std::vector<SupportNode*>>& con
                             }
                         }
                         if (layer_nr == 0 && m_raft_layers == 0) {
-                            double brim_width = !config.tree_support_auto_brim ? tree_brim_width : std::max(0.0, std::min(node.radius + node.dist_mm_to_top / (scale * branch_radius) * 0.5, MAX_BRANCH_RADIUS_FIRST_LAYER) - node.radius);
+                            double brim_width = !config.tree_support_auto_brim ? tree_brim_width : std::max(MIN_BRANCH_RADIUS_FIRST_LAYER, std::min(node.radius + node.dist_mm_to_top / (scale * branch_radius) * 0.5, MAX_BRANCH_RADIUS_FIRST_LAYER) - node.radius);
                             auto tmp=offset(circle, scale_(brim_width));
                             if(!tmp.empty())
                                 circle = tmp[0];
@@ -2032,14 +2032,14 @@ void TreeSupport::draw_circles(const std::vector<std::vector<SupportNode*>>& con
                         has_circle_node = true;
                     }
 
-                    if (node.distance_to_top < 0)
+                    if (layer_nr>0 && node.distance_to_top < 0)
                         append(roof_gap_areas, area);
-                    else if (node.support_roof_layers_below == 1)
+                    else if (layer_nr > 0 && node.support_roof_layers_below == 1)
                     {
                         append(roof_1st_layer, area);
                         max_layers_above_roof1 = std::max(max_layers_above_roof1, node.dist_mm_to_top);
                     }
-                    else if (node.support_roof_layers_below > 0)
+                    else if (layer_nr > 0 && node.support_roof_layers_below > 0)
                     {
                         append(roof_areas, area);
                         max_layers_above_roof = std::max(max_layers_above_roof, node.dist_mm_to_top);
diff --git a/src/libslic3r/Support/TreeSupport.hpp b/src/libslic3r/Support/TreeSupport.hpp
index 322ef66da8..62cce6ffea 100644
--- a/src/libslic3r/Support/TreeSupport.hpp
+++ b/src/libslic3r/Support/TreeSupport.hpp
@@ -406,8 +406,9 @@ private:
     std::vector< std::unordered_map<Line, bool, LineHash>> m_mst_line_x_layer_contour_caches;
     float    DO_NOT_MOVER_UNDER_MM = 0.0;
     coordf_t MAX_BRANCH_RADIUS = 10.0;
-    coordf_t MAX_BRANCH_RADIUS_FIRST_LAYER = 12.0;
     coordf_t MIN_BRANCH_RADIUS = 0.5;
+    coordf_t MAX_BRANCH_RADIUS_FIRST_LAYER = 12.0;
+    coordf_t MIN_BRANCH_RADIUS_FIRST_LAYER = 2.0;
     float tree_support_branch_diameter_angle = 5.0;
     coord_t m_min_radius = scale_(1); // in mm
     bool  is_strong = false;