Northern Ontario Plant Database

Leaf Apices

• Attenuate - a sharp-pointed apex with concave margins that form an angle less than (<) 45 degrees.
• Acuminate - a sharp-pointed apex with straight or convex margins that form an angle less than (<) 45 degrees.
• Acute - an pointed apex with margins that form an angle between 45 and 90 degrees.
• Obtuse - a blunt apex with margins that form an angle greater than (>) 90 degrees.
• Rounded - an curved apex with margins that form a smooth arc.

• Caudate - an attenuate apex with a slender tail-like appendage at the tip.
• Cuspidate - an acute apex with a stiff tip or cusp.
• Mucronate - with a small extension of the midrib barely extending beyond the blade apex.
• Emarginate - with a shallow depression at the apex, not exceeding ? of the distance to the centre of the leaf blade.

• Truncate - a broad, flat apex, abruptly ending at right angles to the midvein.
• Retuse - a rounded summit with a shallow depression at the apex, not exceeding 1/16 of the distance to the centre of the leaf blade.
• Obcordate - apex with prominent, rounded lobes, cut ? to ¼ of the distance to the centre of the leaf blade.
• Cleft - apex divided into rounded or straight-margined lobes, cut ¼ to ½ of the distance to the centre of the leaf blade.