Category Archives: disease

Hackberry Nipples

disease, education

Mrs. A, the friend I visited last Spring in Louisville, migrated back to her native state and is now closer by and in the same growing zone as I. She and her family purchased a modest little farmhouse in a rural area of the state. With the house came a beautiful parcel of land including a veggie lot, small apple orchard, herb garden, mature trees, and established perennial plantings.

Every now and then she’ll ping me with a question about gardening as she is a newcomer to the hobby. She’s been soaking up knowledge like a sponge and I’ve been having a great time chatting with her about all things green and growing. The following was a photo she sent to me from leaves she noticed on a mature tree near the garage. She asked if this was a disease and something they should treat.

073116_hackberrynipple2

Weird, right?! It’s one of those things you poke at with fascination and a touch of “this creeps me out.” There were cylinder-like growths protruding from the underside of the leaves.

ID the Victim

The first thing to do was ID the tree. Many universities have great tree ID keys on their websites. After using the bark, leaves, shape of the tree, and the growing Zone where we are located, we identified the tree as a hackberry (Celtis occidentalis). The hackberry is a hardy shade tree growing up to 60 feet tall. Mrs. A’s hackberry was one of these mature specimens.

What are the Symptoms

Here is another shot of the hackberry leaf. The leaf itself was picked up from the lawn, not from the tree. However, some branches were hanging low enough to notice the leaves were not dry, but did have the same odd growths.
073116_hackberrynipple
Many irregular growths on plants are referred to as “galls.” The plant reacts to a parasite ranging from bacteria to insects, increasing growth hormones. According to the University of Minnesota, “These plant hormones cause localized plant growth that can result in increases in cell size (hypertrophy) and/or cell number (hyperplasia).” The gall is a growth similar to a benign tumor or wart on an animal.

Galls can appear on leaves, stems, twigs, flowers, and buds. This appeared to be a leaf gall, one of the most common in the plant world. UofM summarizes leaf galls as “leaf curls, blisters, nipples, or erineums (hairy felt-like growths) on the upper or lower leaf surface.”

So, this gall growing on the underside of the leaf was a further clue to help Sherlock the situation. The situation seemed hopeful though because most galls are more of a cosmetic blemish than threatening to the health of a plant. Plus, unlike a young plant needing every bit of the nutrients it can collect, this huge hackberry was older and well settled.

Hackberry Gall Psyllids

Searching on The Internets, armed with the name of the tree and the knowledge of galls, eventually landed me on the Nebraska Extension in Lancaster County website. It seemed the culprit was the hackberry gall psyllid.

After overwintering beneath the bark of the tree, adult psyllids  lay eggs on the new growth of spring leaves. When the egg hatches, the young insect begins to feed on the sap of the leaf. This action triggers the forming of the gall, enclosing the insect. The psyllid will remain protected as it feeds throughout the summer.

To Spray or Not to Spray

It depends on the homeowner or gardener as to how comfortable he or she is with the cosmetic alteration of the tree. It was comforting to Mrs. A to know the hackberry gall psyllid was not harming the tree. Because of the large size of the tree and the fact at this stage the galls protect the insects, a foliar spray would have been a waste of time and money. Spraying during spring when the nymphs are emerging would be an option, but the application would have to be repeated over several weeks, again resulting in a huge expense. There are insecticide drenches that can be mixed and applied at the base of the tree during the feeding period of sucking insects. This also is based on the size of the tree so may be impractical due to cost. That money could be put toward new plants! If it were up to this gardener, the tree is not being harmed so I would let nature handle it.

2013 Smart Gardening Conference

compost, disease, education, gardening sites, pest control

MSU Smart Gardening

First a disclaimer: other than having gone through the Master Gardener Volunteer Program this past fall, I do not officially represent the MSU Extensions office. However, as a fledgling Master Gardener Volunteer, I am really excited about what I learned at the conference yesterday and feel it is important to share with anyone interested. Information about best practices in gardening is always changing so no matter how long one has been gardening, there is always more to learn.

What is “Smart Gardening?”

This year the extensions office has been repositioning to focus on Smart Gardening. The concept involves being informed before taking action; we can then put our knowledge of gardening to use with the least amount of negative impact on our environment. Before anyone flies into a rant about dirty hippies, know this approach to gardening is a nice compromise between having a beautiful garden/lawn, being considerate of the rest of us, and saving some $$$. If anything else, my fellow Americans should be happy about that last one.

A Few Key Concepts

We were given a ton of information at the conference spread out over the course of four presentations. The presenters included Joe Lamp’l (PBS’s ‘Joe Gardener’), Dr. Rufus Isaacs  and Dr. Dave Smitley (MSU’s Department of Entomology), and Rebecca Finneran (MSU Extension Consumer Horticulture Educator). I’ll record a lot of info on this blog during the next few weeks while waiting for spring. Here are just a few key points:

Water Management

  • Conserve water through the use of rain barrels.
  • Prevent runoff with rain gardens, green rooftops, and dry creek beds.
  • Reduce the need for watering with the use of mulch.
  • Catch “warm-up” water from within the house to use in the garden.

Compost

  • Reduce need for fertilizer by using compost.
  • 65% of landfill items are recyclable or compostable for backyard bins.
  • Reduce cost of yard waste removal by using grass clippings and leaves in the garden or compost bin.

Fertilizer & Pesticide Use

  • Understand plant requirements first: Right plant; right place.
  • Group plants with similar needs together.
  • Only 3% of insects are harmful; why spray the whole garden?
  • Plant bio-diversity to naturally attract beneficial insects / pollinators.

Smart Gardening Resources

The MSU Gardening in Michigan website is full of free literature on how to practice Smart Gardening at home. Many tips can be put into practice far beyond the Michigan growing zone. Before scalping the lawn, over-fertilizing the garden, or waging chemical warfare on possibly beneficial insects, give the site a look. In the case of a specific gardening question, Michigan residents can call the MSU Extensions Hotline at 1-888-678-3464.

 

Bites & Blemishes

disease, pest control, , , , , , , , ,

One thing I’ve found very annoying about gardening is the fact that plants get sick. I know, there is no such thing as easy, non-maintenance gardening. I am also willing to work for beautiful plants. But, it doesn’t change the fact I fret and even get grumpy about plants being chomped on or made ill.

Both the catnip and the foxglove are showing such signs. I snapped pictures so I can try to puzzle out what’s going on with them once I was back to the computer. With the catnip, I’m thinking a combo of the wet spring and dense foliage is causing a type of mildew/blemishes on the leaves. I don’t know yet what is stressing the foxglove. At first I thought it may be some frost damage from a cold snap we had after the plant had sent out it’s first new shoots. Now I think it’s some kind of insect. Will have to research it more.
Edelweiss are budding in the back bed and yellow day lilies are going to open any day in the sidewalk bed. The forget-me-not seedlings are well on their way in Loki’s bed and the moonflower seedlings and new black barlow columbine in the gate bed are growing well. The rose bush in the southwest bed bloomed! The flowers are a very pale pink that turn almost to white after opening.
Also, this week I brought home some different types of ground cover from a co-worker’s garden. Our lot now has some vinca, chameleon plant and bishop’s weed.