Plants facing aphids and other problems

Aphids and other problems facing plants

The grass was green until the cool-down of this week. It has been hot and humid, with plenty of rain, since then. e In full bloom is the ancient peegee-hydrangea shrub at our corner. In backyards and at markets, sweet corn, tomatoes, and melons are all in harvest mode. Summer is full of energy.

Northeast Ohio is home to many flower planters. Calla lilies and petunias as well as creeping daisies and begonias are on display along the streets of cities. Even tiny mini-hydrangeas can be found. They are quite beautiful despite the summer heat that discourages many gardeners. City gardeners deserve kudos; enjoy shopping, dining, and exercising.

1. Oleander aphids (Aphis neri).

What are oleander aphids eating? Oleanders and their relatives are the main food source for oleander aphids. This is why Ohio gardens are so important. These aphids can only be fed by members of the Apocynaceae family (dogbane). This includes the perennial groundcover Vinca Minor and its associated annual genus Catharanthus. There are many colorful cultivars.

  • These insects also eat Amsonia and, according to recent DNA evidence, milkweeds. They have been reclassified as Asclepiadaceae.
  • This familial host range of oleander-aphids has always been an example of how insects coevolved with their host plants. It can even be used to inform us about the relatedness of plants (e.g. the folding in of milkweeds within the Apocynaceae).
  • The oleander aphid, which is black-antennaed, on Gomphocarpus milkweeds at Wooster. The aphids suck the sap and then exude sticky sugary honeydew that can sometimes be colonized by mold fungi.
  • You’ll not see oleander-aphids in serious plant health issues. They are unlikely to pose a threat to monarchs by removing their host plants. This may not always be the case and pestilence can be seen in different places. However, I believe that monarchs and milkweeds should not be afraid of the aphid.

2. How do you see a problem with a plant?

Cankered areas on a maple tree and dogwood, the “late coming”, of flowers, and the mosaic-like yellowing of some leaves in my Pawpaw patch.

Botryosphaeria canker

  • The Botryosphaeria canker (discolored, dead, and inwardly oriented areas of bark) that appear on yellow-twigged shrub dogwoods are caused by the Botryosphaeria fungal infection. It can be very damaging to the area of the plant where the canker is located.
  • Pruning is the only way to get rid of the canker, especially if it extends all the way around the stem. However, pruning would effectively kill the plant.
  • Cactus. Its spring dieback to the ground was mistaken for the loss of the scion.

Rejuvenation pruning

  • The tree is pruned to a few inches above ground each fall. This is called rejuvenation pruning.
  • The tree should not be grafted as it will grow on its own roots and would soon flower.

3. Yellowing and mosaic blotching

The third problem is still unresolved. It involves yellowing and mosaic blotching. Although the mosaic pattern of yellow and green looked like a viral infection in plants. It was strange: Some parts of the plant’s foliage were completely unsymptomatic while others were severely affected. There was no rhyme or reason to this pattern.

Plant viral testing should not be routinely performed if the virus is unknown.

Plants have different diagnoses, prognoses, and levels of uncertainty. The problems that plants have and how they are able to shed light on them in your yard might suggest that not all problems with plants, such as politics, are global and minor. Some problems are actually specific to the plant concerned. For example, giant redwoods in California ( SequoiadendronGiganteum). They are endangered despite their beauty and irreplaceable status in the national consciousness.