III.6 Longitudinal Section of an Herbaceous Stem

Aim

To observe the longitudinal arrangement of tissues in a soft plant stem, including epidermis, vascular elements, and pith.

Specimen & Apparatus

• Fresh herbaceous stem (e.g. cleavers, garlic mustard, or similar)
• Sharp blade or razor
• Slide and coverslip
• Water
• Compound microscope

Method

1. Select a fresh stem segment, preferably including an internode.
2. Secure the specimen to maintain alignment (e.g. lightly held or fixed at the ends).
3. Using a sharp blade, draw along the length of the stem to obtain a thin longitudinal section.
4. Transfer the section to a slide with a drop of water.
5. Apply a coverslip carefully.
6. Examine under low power to observe general structure.
7. Increase magnification to examine finer detail.

Observations to Make

• Alignment of cells along the axis of the stem.
• Differences between outer (epidermal), intermediate (cortical), and inner (pith) tissues.
• Presence of elongated, tube-like vascular elements.
• Surface features such as hairs or projections.
• Differences between node and internode regions (if present).

⚠️ Safety: Please read the Safety & Disclaimer page before attempting this exercise.