Beyond the Lion's Tail: A Guide to Pruning Fruit Trees for Optimal Growth and Yield

The Lion’s Tail Dilemma: Avoiding Common Pruning Mistakes

Pruning fruit trees is a rewarding yet sometimes perplexing endeavor. While the goal is often to create a strong, productive tree, missteps can lead to undesirable results, such as the dreaded ‘lion’s tail’ effect – an overabundance of foliage at the top with sparse growth below. This article delves into the common pitfalls of pruning, particularly in young fruit trees, and provides guidance on how to correct course and foster healthy, well-structured trees.

Understanding the ‘Lion’s Tail’ Effect

The term ‘lion’s tail’ describes a tree’s appearance when most of its foliage concentrates at the end of its branches, resembling a lion’s tail. This often results from improper pruning techniques that stimulate excessive upper growth while suppressing lower branch development. Several factors contribute to this, including:

• Excessive Heading Back: Repeatedly cutting back the terminal buds (the growing tips) of branches encourages the development of multiple shoots just below the cut. This stimulates vigorous growth at the ends of the branches, diverting energy away from the interior and lower portions of the tree.
• Insufficient Thinning: Thinning involves removing entire branches back to their point of origin or a larger branch. This opens up the canopy, allowing sunlight and air to penetrate. Lack of thinning promotes overcrowding, shading out lower branches and inhibiting their growth.
• Ignoring Branch Angle: The angle at which a branch emerges from the trunk significantly influences its growth. Branches with wide angles (approaching 90 degrees) tend to be stronger and more productive, while those with narrow angles (closer to the trunk) are weaker and prone to breakage. Pruning practices must consider and encourage optimal branch angles.

Common Pruning Mistakes and How to Avoid Them

Several pruning practices can inadvertently lead to the lion’s tail effect. Recognizing these errors is the first step in correcting them.

• Over-Pruning in General: While pruning is essential, excessive removal of growth, especially in young trees, can shock the tree and lead to unbalanced growth. It is crucial to prune with a specific purpose and avoid taking off too much at once.
• Selecting Too Few Scaffold Branches: Scaffold branches are the primary branches that form the tree’s structural framework. Choosing too few can lead to overly vigorous growth in those selected branches, exacerbating the lion’s tail effect. A good rule of thumb is to aim for 3-4 well-spaced scaffold branches.
• Topping Without Considering Branch Orientation: Topping, or cutting the central leader (the main upright stem), can be a useful technique, but it must be done strategically. Always cut to an outward-facing bud to encourage outward growth. Incorrect cuts can lead to inward-growing branches, which will further overcrowd the tree and promote the lion’s tail.
• Neglecting the Lower Canopy: Lower branches are crucial for overall tree health and fruit production. They help shade the trunk, protect the soil, and contribute to photosynthesis. Failure to encourage growth in the lower canopy is a significant contributor to the lion’s tail effect.

Corrective Measures and Best Practices

If you suspect your fruit trees are developing a lion’s tail, or if you wish to prevent this issue, consider these strategies:

• Prioritize Thinning over Heading: Favor thinning cuts over heading cuts. Thinning removes entire branches, opening up the canopy and allowing sunlight and air to reach all parts of the tree. This encourages balanced growth.
• Gradual Approach: If you’ve been over-pruning, avoid making drastic changes at once. Over time, make the needed corrections gradually.
• Prune in Late Winter or Early Spring: This is generally the best time to prune fruit trees, as the trees are dormant and less susceptible to disease. However, some pruning can be done during the growing season to address specific issues like crossing branches or water sprouts.
• Train Young Trees: Training young trees is essential for establishing a strong framework.
• Branch Spacing and Angle: Pay close attention to branch spacing and angle. Wide-angled branches are preferable. Use spreaders or weights to encourage wider angles in young trees. Avoid branches that cross or rub against each other.
• Encourage Lower Branch Development: To encourage lower branch growth, you can:
  • Use Spreading Techniques: Spreaders or weights can be used to angle the branches downward, reducing their vigor and promoting the development of buds along the branch.
  • Reduce Upper Branch Vigor: Prune the upper branches more heavily than the lower ones to redirect energy to the lower parts of the tree.
  • Avoid Excessive Heading: Minimize heading cuts, especially in the upper canopy.
  • Sunlight and Air Circulation: Pruning to improve sunlight penetration and air circulation is essential for the health and productivity of your fruit trees. Ensure branches are not overly crowded.

Addressing Existing Lion’s Tail Symptoms

If your trees are already showing signs of lion’s tail, here’s a plan of action:

1. Assess the Situation: Carefully examine your trees. Note the density of foliage, the spacing of branches, and the angle of the branches. Identify any crossing or rubbing branches.
2. Thinning Cuts: Make thinning cuts to remove some of the branches from the top of the canopy. This will allow more sunlight to penetrate and encourage the development of lower branches.
3. Lower Branch Intervention: If lower branches are present but weak, consider lightly pruning the upper branches to shift some of the energy to the lower sections of the tree. Use spreaders or weights to encourage the growth of lower branches.
4. Re-evaluate Pruning Techniques: Analyze your past pruning practices. Identify any mistakes you may have made, such as excessive heading or insufficient thinning. Adjust your approach accordingly.
5. Patience is Key: Correcting the lion’s tail effect takes time. Be patient and consistent with your pruning efforts. It may take several years to fully reshape the tree.

Specific Considerations for Plum and Cherry Trees

Plum and cherry trees have unique growth habits. They are prone to certain diseases and pests, and their fruit production can be affected by pruning choices.

• Pruning Time: Prune plums and cherries after they have finished fruiting. This is usually in late summer or early autumn.
• Disease Prevention: Both plums and cherries are susceptible to diseases. Always use clean, sharp pruning tools and disinfect them between cuts, especially when dealing with diseased wood. Prune to promote air circulation and sunlight penetration to minimize the risk of fungal diseases. Remove any dead or diseased wood promptly.
• Fruiting Habits: Plum trees often bear fruit on spurs (short, stubby shoots) that develop on older wood. Cherry trees typically fruit on spurs as well, but they also produce fruit on one-year-old wood. Avoid excessive pruning of older wood, as this can reduce fruit production.
• Branch Angle: Both plum and cherry trees benefit from wide-angled branches. Use spreaders or weights to encourage the desired angles.

Conclusion

Pruning fruit trees is an ongoing process that requires observation, understanding, and patience. By avoiding common mistakes, such as excessive heading and insufficient thinning, and by implementing the corrective measures outlined above, you can help your trees develop a strong structure, produce abundant fruit, and avoid the undesirable lion’s tail effect. Remember to adapt your pruning techniques to the specific needs of your tree species and to the unique characteristics of your garden. By following these guidelines, you will be well on your way to cultivating healthy, productive, and beautiful fruit trees for years to come.