diff --git a/src/monmove.c b/src/monmove.c
index c6babe5ca..90b4f33c1 100644
--- a/src/monmove.c
+++ b/src/monmove.c
@@ -14,8 +14,10 @@ STATIC_DCL int FDECL(disturb, (struct monst *));
 STATIC_DCL void FDECL(release_hero, (struct monst *));
 STATIC_DCL void FDECL(distfleeck, (struct monst *, int *, int *, int *));
 STATIC_DCL int FDECL(m_arrival, (struct monst *));
+STATIC_DCL int FDECL(count_webbing_walls, (XCHAR_P, XCHAR_P));
 STATIC_DCL boolean FDECL(stuff_prevents_passage, (struct monst *));
-STATIC_DCL int FDECL(vamp_shift, (struct monst *, struct permonst *, BOOLEAN_P));
+STATIC_DCL int FDECL(vamp_shift, (struct monst *, struct permonst *,
+                                  BOOLEAN_P));
 
 /* True if mtmp died */
 boolean
@@ -742,15 +744,21 @@ xchar nix,niy;
     return FALSE;
 }
 
-/* returns the number of walls in the four cardinal directions that could hold up a web */
-int
-count_webbing_walls(x,y)
-xchar x,y;
+/* returns the number of walls in the four cardinal directions that could
+   hold up a web */
+STATIC_OVL int
+count_webbing_walls(x, y)
+xchar x, y;
 {
-#define holds_up_web(x,y) ((!isok((x),(y)) \
-                            || IS_ROCK(levl[(x)][(y)].typ) \
-                            || levl[(x)][(y)].typ == IRONBARS) ? 1 : 0)
-    return holds_up_web(x, y-1) + holds_up_web(x+1, y) + holds_up_web(x, y+1) + holds_up_web(x-1, y);
+#define holds_up_web(X, Y) ((!isok((X), (Y))                              \
+                             || IS_ROCK(levl[X][Y].typ)                   \
+                             || (levl[X][Y].typ == STAIRS                 \
+                                 && (X) == xupstair && (Y) == yupstair)   \
+                             || (levl[X][Y].typ == LADDER                 \
+                                 && (X) == xupladder && (Y) == yupladder) \
+                             || levl[X][Y].typ == IRONBARS) ? 1 : 0)
+    return (holds_up_web(x, y - 1) + holds_up_web(x + 1, y)
+            + holds_up_web(x, y + 1) + holds_up_web(x - 1, y));
 #undef holds_up_web
 }
 
@@ -1448,14 +1456,22 @@ postmov:
             }
         }
 
-        /* maybe a spider spun a web */
-        if (webmaker(ptr) && !t_at(mtmp->mx, mtmp->my)) {
-            int prob = ((ptr == &mons[PM_GIANT_SPIDER]) ? 15 : 5) *
-                (count_webbing_walls(mtmp->mx, mtmp->my) + 1);
-            if (rn2(1000) < prob) {
-                struct trap* trap = maketrap(mtmp->mx, mtmp->my, WEB);
-                if (trap && canspotmon(mtmp)) {
-                    pline("%s spins a web.", upstart(y_monnam(mtmp)));
+        /* maybe spin a web -- this needs work; if the spider is far away,
+           it might spin a lot of webs before hero encounters it */
+        if (webmaker(ptr) && !mtmp->mspec_used && !t_at(mtmp->mx, mtmp->my)) {
+            struct trap *trap;
+            int prob = ((ptr == &mons[PM_GIANT_SPIDER]) ? 15 : 5)
+                      * (count_webbing_walls(mtmp->mx, mtmp->my) + 1);
+
+            if (rn2(1000) < prob
+                && (trap = maketrap(mtmp->mx, mtmp->my, WEB)) != 0) {
+                mtmp->mspec_used = d(4, 4); /* 4..16 */
+                if (cansee(mtmp->mx, mtmp->my)) {
+                    char mbuf[BUFSZ];
+
+                    Strcpy(mbuf,
+                           canspotmon(mtmp) ? y_monnam(mtmp) : something);
+                    pline("%s spins a web.", upstart(mbuf));
                     trap->tseen = 1;
                 }
             }