Methods for Controlling Rose Sawfly
For many girls, the knowledge of rose sawfly control is a small gardening tip. Here is a comprehensive introduction to follow.
In April, roses enter the bud formation stage. Watching the small flower buds swell day by day fills one with anticipation. However, you must not lower your guard because there is a "rose killer"悄悄 approaching, or it may have already moved into your garden. This is the rose sawfly.
Getting to Know the Rose Sawfly
To control the sawfly and protect our roses from damage, we must first understand and recognize the sawfly. As the saying goes, "Know yourself and your enemy." Many gardening enthusiasts mistake the rose leafminer for the sawfly, but there is a big difference between them. The following image shows the rose leafminer.
The rose leafminer usually becomes active after the summer begins, and it also lays eggs on the rose branches. However, its eggs and larvae do not cause as much harm to roses as the sawfly. After the eggs of the leafminer hatch, it's just a group of small caterpillars eating leaves, and they can defoliate a rose bush in just two to three days, but they won't cause the branches to wither. By making frequent inspections during the summer and applying insecticide promptly, the problem can be solved. The difficulty level of management is negligible.
The rose sawfly is a completely different story. This pest is particularly讨厌, to the point where... It's like you've nurtured a beautiful flower ball that's about to burst into bloom, and then your plastic sister comes along with a pair of scissors, snipping here and there, and voilà, the flowers are gone, and so is the flower ball! Imagine how frustrating that would be...
The image below shows the much-detested "rose killer" — the rose sawfly.
The body of the sawfly is longer and more slender, and it specifically chooses robust branches to lay eggs. After the eggs hatch and the larvae begin to feed inside the tender branches, the rose branches will show signs of dehydration and drooping. As shown in the following image↓↓
Once the tender branches of the rose show signs of dehydration and drooping, they are basically beyond salvation. Although there have been shares of the "acupuncture" method to save them, the success rate is not high, and even if saved, it greatly affects the growth of the flower buds. Therefore, for the rose sawfly, the control work still needs to be done before the sawfly lays eggs.
The sawfly is a flying insect, and it is very small, so even if it is in your garden, it is difficult for gardening enthusiasts to detect it. What we often see are the drooping rose branches. Therefore, the difficulty of controlling the sawfly is relatively high, and to date, there is no 100% effective method to control the rose sawfly. However, a new method for controlling the sawfly has been discovered this year, and I hope this control idea can help you.
Methods for Controlling the Rose Sawfly
The rose sawfly is more active on sunny days, usually between 10 a.m. and 1 p.m., which is also the peak time for laying eggs. During rainy days and in the early morning or evening, the sawfly's activity is relatively less frequent. The sawfly also likes to stay still when the weather is bad and the temperature is low.
In the Jiangsu, Zhejiang, and Shanghai regions, the middle to late April each year is the most severe period for sawfly damage, which also coincides with a high number of rainy days. It is often found that after a rainy day, many tender rose branches will droop. This is actually because the eggs laid by the sawflies have hatched, and the larvae have bored into the inner tissue of the branches. However, because it has been raining and the branches have been hydrated, they can still manage to stand. But as soon as the sun comes out, the branches where the eggs were laid will all collapse.
Therefore, the best time to control the rose sawfly should start from the end of March to early April and continue until the end of April. The main control strategies are as follows:
1. Eradicate or Repel Adult SawfliesIf adult sawflies do not lay eggs on our roses, then all problems will cease to exist. Therefore, eradicating or repelling adult sawflies is what we should focus on.
①. Spraying Pesticides and Hanging Sticky Traps
Controlling the rose sawfly with pesticides should start in winter, but even if we have cleaned the garden in winter, sawflies may still fly in from elsewhere in the spring. Therefore, during the peak period of sawflies in April, we still need to persist in spraying pesticides to eradicate the adults, although the effectiveness of the spray may not always be satisfactory.
Since sawflies do not move in groups and it is unknown when they will come, if we are to eradicate the adult sawflies with pesticides, we may need to spray every 2-3 days. The recommended pesticide is Thiacloprid · Beta-cypermethrin, which is effective against common pests. The spraying time should be around 9 a.m. or in the evening. After spraying, sawflies that come into contact with the solution will be killed instantly, although this method is not very environmentally friendly.
Therefore, many gardening enthusiasts recommend hanging yellow boards in the hope of trapping the sawflies. However, to be honest, this really depends on luck. Sawflies do not have a clear preference for yellow, so while yellow boards are good for trapping pests, they may not be very effective against sawflies.
②. Repelling Adult Sawflies with Mugwort Mosquito Repellent
Recently, I accidentally discovered a new method for repelling adult sawflies, which is to use mugwort mosquito repellent coils.
The story goes like this: A few days ago, a group of large, plump bees suddenly appeared in my courtyard. I didn't know what kind of bees they were at the time, but there were many of them flying around my roses, and I was worried about whether they would have a bad effect on the roses. So I quickly hung some yellow boards to try to trap them, but to my frustration, they just flew around the yellow boards and wouldn't go up...
Then I thought about spraying insecticide, but it was noon, the sun was very strong, the rose branches were very tender, and the pesticide water would probably burn the leaves if sprayed. So I gave up on that idea.
Suddenly, a brilliant idea struck me, and I remembered that I had some mugwort mosquito repellent coils left over from last year. I quickly lit six of them and placed them in different parts of the courtyard, thinking that even if they didn't kill these large bees, they would probably make them uncomfortable and not want to stay here.
The mugwort mosquito repellent coils burned for about two hours, and the courtyard was filled with the scent of mugwort. When the coils were finished, the large bees were gone, and in the evening, my mother-in-law even found the bodies of the bees on the ground.