Xtremehorticulture

Leaf Miner Damage on Many Different Plants

Q. In my morning walk around the garden, I found this unusual pattern on the leaves of my Arabian Jasmine.  Do you have any thoughts on what might have caused this? Serpentine leaf miner damage on Jasmine leaf. A. This is one of the leaf miners. Because of its snakelike pattern of damage caused on the leaves, this particularly matter is called the “Serpentine” Leaf Miner. Leaf miners in general are the immature of moths or a flies but in this case of the Serpentine Leaf Miner the culprit is a fly. The fly’s lifecycle has four stages; the adult fly with wings for finding a sex partner, the egg, maggot, pupa which finally turns into the adult again. The serpentine leaf miner adult fly punctures the leaf surface. It inserts its eggs inside the leaf. This is a perfect warm and wet environment for the egg to hatch into a very tiny maggot. Food and moisture are all right there and protected from predators inside the leaf! This tiny maggot tunnels between the upper and lower surface of the leaf in this wet juicy nutrient rich layer where it feeds at the same time.  Leaf miner attacking these leaves in Afghanistan If you hold the leaf up to the light you will see that these serpentine patterns are tunnels, have nothing in them, but are surrounded by dark, green leaf tissue. The second thing you will see is that this serpentine tunnel gets wider along the feeding path and shows you the direction this maggot has moved inside the leaf; the tunnel is narrower when it is small and gets wider as it grows. At the end of this tunnel this maggot stops feeding and pupates into the adult fly and exits the leaf.   More leaf miner damage To control this pastor not depends on the value of the damage it creates. Leaf miners also attack weekly green vegetables like lettuce and spinach. In cases like these, we don’t want any damage or very little because we’re going to eat these leaves. This insect is also causes damage to some fruit trees like citrus and ornamentals like roses, annual flowers and in your case Jasmine, where leaf damage can be tolerated more.   Leaf miner damage in citrus leaves So the tolerant to damage of leafy greens is very low and start to control this pest in a variety of ways as soon as damage is seen. Control can be as simple as removing leaves as soon as you start seeing the damage. It takes a while for this past to create these tunnels so with a little bit of diligence, leaf removal works extremely well. Removing leaves as soon as you see damage reduces the level of adults and is very efficient at minimizing damage. When you remove the leaves, don’t throw them on the ground but put them in the trash or destroy them immediately. Heavy leaf miner damage. This damage is heavy enough that it might require spraying for prevention in the next planting. You can spray the leaves with chemicals, and this is done frequently on leafy greens vegetables grown for commercial production to protect the crop, but if you don’t need to spray then don’t. Understand and live with the damage if it’s minor and use leaf removal if it starts to get out of control.

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Sago Palm aka Cycad Growing in Containers Needs Soil Changed to Stay Healthy

Q. The cycad I bought in a container a few years ago is turning yellow even though I moved it out of direct sun and into the dappled shade of a vitex tree. Can you advise whether I still need more shading to correct the yellowing? I’m afraid to plant it in the ground because it might freeze. Cycad or sago palm, needs the soil renewed if grown in containers. I would recommend amending or renewing it every three years. Take the plant out of the container during cool weather, wash off the roots, renew or replace the soil with a good soil/ this will improve its health. Healthier plants can withstand environmental sress better than those  in poor health. A. I don’t think the yellowing is a problem from intense sunlight. This plant can handle full sun in our Mojave Desert with no problems if the soil has been prepared adequately, organic amendments are added to the soil every year or two and water is available when needed. It’s easier to grow, however, on the East sides of buildings where it gets some protection from the late afternoon sun.             From your picture, it seems it is growing in the same container that came from the nursery. If this is true, all the organics in that original soil are gone. Even if you are adding fertilizer to the container, the plant leaves yellow because the soil is “worn out”. Basically, the plant is growing in the container hydroponically (only water and whatever fertilizer it gets).             It is important to add organic amendments to all soils on a regular basis to maintain good plant health, improve its tolerance to our harsh desert climate and stay resistant to diseases.             Plants grow better and are healthier (they can withstand more problems) if they are grown in the ground and in a healthy manner. Your cycad is growing in an old, “tired” soil that has not been amended, in a container that’s too small and who knows if it’s getting water when needed.             Pick a spot for it and get it planted. Plants growing in containers are difficult to manage. In the ground, it can grow in full sun if surrounded by other irrigated plants. This plant will be healthier if the soil is covered with woodchips rather than rock. It is not a desert plant for sure, so it needs to be planted and watered with other non-desert plants and cared for in a non-desert way.             These plants will tolerate temperatures as low as 20°F but may show some winter damage (bronzing) to the leaves at 25F. Remember, winter cold is worse if the plant is growing in a windy location.             When planting it this Fall, use a quality compost and mix it equally with soil taken from the planting hole. When planting, use this amended soil and flood the hole with water as soil is added. Make sure it’s planted at the proper depth; not too shallow nor too deep.             Cover the soil surrounding it with woodchips from local trees trimmings. These will degrade over time and add more organics to the soil. Your cycad will appreciate this! Fertilize it lightly once a year with a tree and shrub or lawn fertilizer. Apply it under the leaves, not too close to the trunk, and water it in.             Leaves that are yellow will stay yellow until removed in a couple of years when the plant gets older and bigger. But the new growth coming from the trunk should be dark green if planted correctly. This new growth eventually replaces yellow leaves as they are removed. Water the same as you would other trees and shrubs in the landscape. Apply about 5-10 gallons of water each time it is irrigated.

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Holes in the Ground in July

Q. I found many holes scattered in bare ground at one of the property I maintain. They are small, perhaps the size of a penny. I have attached a photo and hope you can help me identify what could be doing this. I don’t want to hurt any pollinators. A. It’s mid-July now and I have been hearing the buzz to attract females from male cicadas since around the first of the month. I think what you are seeing are emergence holes of cicadas. The immature cicada “grub” lives underground and feeds on tree roots such as ash.             Most people know the 17-year, periodical cicadas but there are other cicadas which emerge every year. The cicadas are nicknamed “dog day cicadas”, or annual cicadas, because they emerge every year during the heat of summer.              That buzzing noise is used to attract females for mating and eventual laying of eggs. The eggs of cicadas are inserted by females into slits cut into small tree branches. Sometimes the small branches die from the damage caused an egg laying combined with the heat of the summer.

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