Sunday, November 11, 2018 0 comments By: Jack Downer

Dealing with Acorns in Your Landscape

Dealing with Acorns in Your Landscape
Tom Ingram: Ask a Master Gardener
Sunday, November 11, 2018
Q: What is up with all the acorns this year? When the wind blows, it sounds like hail hitting the roof! NM
A: I was raking leaves off the patio recently, and I don’t remember the last time I needed a shovel to pick up all the acorns. So at least in my yard and the yards of my neighbors, I agree, this year we seem to have more acorns than usual.
However, just because some of us are experiencing a bumper crop, this may not be true throughout the region. These “mast” years (as these large acorn crops are called) can be localized, as the main contributor to fruit production is the weather, and as we know, weather can vary depending on your location and particular microclimate. However, one large oak having a particularly good year can drop up to 10,000 acorns in a mast year. And, yes, that can get noisy on the roof!
The primary weather factors affecting acorn development are spring frosts, summer droughts and fall rains. When the oak trees determine the danger of a spring frost has passed, they begin to flower. Oaks are what we call monoecious. This means that a single oak contains male and female flowers.
If you have an oak tree in your yard, you are probably familiar with the male oak flower as they are those long, worm-like growths that contain a number of flowers arranged like beads on a string. These flowers produce the pollen that tends to give our patios and cars a green tint in the spring. In contrast, the female flowers are quite small and often resemble leaf buds.
The spring winds blow pollen from tree to tree pollinating the female flowers. Interestingly, the acorns of white oaks mature within the year while acorns of red oaks mature over a period of two years.
Some of these acorns may grow up to become oak trees, but others will serve as a source of protein for blue jays, wild turkeys, rodents, deer and bears. Secondarily, if we have a year of larger than normal acorn production, depending on the reproduction cycles of the animals, we can expect surges in the populations of mice, squirrels, chipmunks, deer, bears, turkeys, etc. While this may be good news for some, unfortunately, a rise in mouse and deer populations can secondarily contribute to an increase in the tick population as well.
Even though the noise from the shower of acorns can be unsettling and the quantity we need to clean up in our yards a nuisance, these acorns remain an important part of our natural ecosystem.

Garden tips
  • Leftover garden seeds can be stored in an airtight container in the refrigerator or freezer until next planting season. Discard seeds more than 3 years old.
  • The garden centers still have large selections of spring-blooming bulbs for sale. If you intend to plant bulbs, buy them and plant soon. Tulips can still be successfully planted through the middle of November.
  • Be sure to keep leaves off newly seeded fescue. The sprouts will die without sun and air exposure.

Sunday, October 28, 2018 0 comments By: Jack Downer

Fall Gardening Tips For the Homeowner

Fall Gardening Suggestions
Brian Jervis: Ask a Master Gardener
Sunday, October 28, 2018
Q: I am trying to get my yard, flowerbeds and garden ready for winter. What are some of the things that should be at the top of my list to do (and not do)? — Rick A., Tulsa
A: Good question. Many people ask us about this about now. There are many things that we as gardeners can be doing right now to get ahead of old man winter, who will soon be knocking at our doorstep. Here are a few:
• Seed/re-seed fescue: This is a tough call. Theoretically, the time has passed to do this (up to mid-October) but, if we were to have a mild late fall/early winter, seeds may still germinate. However, if it should turn cold quickly, they will not germinate. Check your weather crystal ball to decide.
• Keep leaves off of newly seeded fescue to prevent damage to the sprouts. A great way to do this is to shred them into small pieces using a recycle-type lawn mower.
• Mow and neatly edge warm-season grasses (i.e. Bermuda, Zoysia, etc.) before the first killing frost.
• Plant container-grown trees and shrubs this month. Fall is generally the best time to plant. At this time, the plants have no energy drain to produce leaves and can concentrate on growing a root system until the soil gets cool in winter. They are better prepared for spring growth and summer stress if planted in the previous fall.
• Plant cool-season annuals like pansies, ornamental cabbage, snapdragons and dusty miller. It is also not too late to plant tulip bulbs for spring color.
• Plant cool-season veggies: broccoli, cauliflower, lettuce, kale, chard, cabbage, collards, spinach, radishes, onions, garlic, turnips, beets and carrots.
• Prune herbs like rosemary, thyme, and sage; prune vegetables such as asparagus and rhubarb, as well as blackberries.
• Divide/plant peonies, daylilies, ornamental grasses, hostas and other spring-flowering perennials. Dig and store tender perennials (i.e. dahlias, caladiums, etc.) in a cool, dry location. Heavily mulch cannas and elephant ears.
• Mulch all beds or plant a cover crop (e.g. rye or vetch) to help moderate soil temperature, increase levels of organic materials to add nutrients, protect the soil from erosion and suppress weed growth. And planting legumes in your garden (e.g. clover, field peas) can increase the levels of available nitrogen for garden vegetables next spring.
• Pull up all dead plants and remove evasive weeds.
• Cover water gardens with either netting or a pond cover to keep out falling leaves.
• Remove garden debris to prevent many garden pests and diseases from overwintering in these materials.
• Prepare your garden soil for spring by tilling. This will break up weeds and expose otherwise hidden grubs.
• Clean up and store garden tools.
And there are a few things that we should NOT do right now, such as:
• Do not trim rose bushes. Given a few warm days that might occur afterward, those new cuts may spawn new growth, which will be readily killed by the first freeze. This can cause an attractive location for disease to enter the plant. Exception: Prune out dead or diseased limbs on trees and shrubs.
• Do not plant bare-root trees at this time. Wait for spring.
• Do not fertilize warm-season grasses or garden beds. Wait for spring.

Sunday, October 14, 2018 4 comments By: Jack Downer

Twig Girdler Insects

Limbs on Ground Under Tree May Be Due to Twig Girdler Insect
Tom Ingram: Ask a Master Gardener
Sunday, October 14, 2018
Q: I have been finding the tips of branches underneath my trees that look like they have been chewed off. What is causing this? DK
A: The culprit is likely an insect called a twig girdler. Adults are long-horned beetles ranging from 1/2 to 5/8 inches in length. They are grayish brown with antennae typically at least as long as the body. The larvae are whitish, cylindrical, legless grubs that grow to about 3/4 inch in length.
Twig girdlers typically prefer pecan, hickory, persimmon and elm. But, they will also enjoy oaks, honey locust, hackberry, poplar, dogwood, and various fruit trees.
This time of year it is not unusual to see these chewed off branches on the ground around trees the twig girdlers call home. Preferred branches tend to be 1/4 to 1/2 an inch in diameter.
Adult twig girdlers emerge from late August to early October and begin to feed on the tender bark found near the branch ends. While feeding they find a mate and the female deposits her eggs underneath the bark.
There are typically three to eight eggs deposited in each twig, but they may contain up to 40 eggs.
The females live around six to 10 weeks and repeat this process several times laying up to 200 eggs that begin to hatch in about three weeks.
Eggs cannot survive in a living twig, so the girdler chews almost all the way through the branch causing the branch to die. It then typically falls to the ground due to its weight or from the wind.
After hatching, the larvae overwinter in the dead twig, feeding on the woody portion of the branch.
After a 12- to 14-day pupation period during August and September the following year, the adult chews a hole in the bark to escape and the process begins again.
It is not uncommon to see the ground almost covered with twigs in heavily infested trees. Young trees can take on a deformed appearance over the years due to a twig girdler infestation. This girdling not only affects the beauty of the tree but can also reduce yields in fruiting trees.
If you are finding these chewed off branches under your trees, your best strategy is to pick up those twigs and throw them away. This removes the insect from your yard and prevents the larvae from maturing and doing damage again next year.
Garden tips
 Plant container-grown trees and shrubs this month. Fall is generally the best time to plant. At this time the plants have no energy drain to produce leaves and can concentrate on growing a root system until the soil gets cool in winter. They are better prepared for spring growth if planted in the previous fall.
 Check and treat houseplants for insect pests before bringing inside. Look at the roots and re-pot those, which are root bound. Irrigate the soil thoroughly before bringing inside.
 There is still time to plant radishes and mustard in the fall garden.

Sunday, September 30, 2018 0 comments By: Jack Downer

Fall is the Best Time to Plant Trees

Planting Trees in Fall
Allen Robinson: Ask a Master Gardener
Sunday, September 30, 2018
Q: Is it true that fall is a good time to plant new trees? If so, what do I need to do to be successful? Alex R., Tulsa
A: Fall is clearly the best time to plant most container-grown deciduous trees and those with balled and burlapped (B&B) root balls. This is because, in the fall, the trees have huge energy stores that are used for growing new roots rather than producing leaves and fruit. This will allow the tree to enter the following growing season much better able to handle the summer stresses. Also, although the air temperatures are dropping, the ground temperatures are still warm enough to encourage good root development for some time. The exception to this rule is that evergreen trees and bare-rooted plants should be planted in early spring.
Of all of the newly planted trees that die in the first few years, the problem is almost always due to faulty planting techniques and inadequate aftercare. So let’s discuss this.
First, it is best to dig a wide but shallow, saucer-shaped hole two to three times the diameter of the tree’s root ball and no deeper than the root ball itself. If you simply dig a hole the size of the root ball, particularly in clay soil, it will be similar to planting it in a clay pot and the tree will be either too dry or too wet much of the time. If you are planting in shallow clay soils, the hole should be shallow enough to elevate the crown of the root ball 2-3 inches above grade to help with overall root system drainage.
When planting trees, it is recommended that you use only native soil for backfill. Studies have shown that trees do better if no amendments are added back to the native soil, as it may delay establishment and promote disease. If you decide to fertilize, apply a slow-release type only to the top of the soil after planting.
Eliminating grass from the tree’s base significantly improves growth rate and health. After planting, apply 2-4 inches of loose mulch in a 4- to 6-foot circle around the base of the tree and keep it well-mulched for the first three years. This circle will keep unwanted grass away from the dripline and commercial weed eaters away from the tree trunk.
All newly planted trees need supplemental watering for the first three years until a mature root system develops. They need at least 1 inch of water per week and more if extremely hot and windy conditions exist. Wilting of the trees’ leaves may indicate a need for more water, but be aware that too much water can also produce wilting. If in doubt, simply feel the sub-soil.
If the tree is on a slope or in a windy area, stake it only until the tree feels firm in the ground, which could take up to one year. After the first growing season, remove all stakes. If not removed, the stakes will adversely affect the tree’s structural integrity and delay tree growth.
For more detailed information on this subject, see OSU Fact Sheet L-440 (Tree Planting Guide).
Garden tips
 You can continue to replant or establish cool-season lawns like fescue until mid-month. The mowing height for fescue should be lowered to approximately 2½ inches for fall and winter cutting.
 Plant cool-season annuals like pansies, ornamental cabbage or kale, snapdragons and dusty miller when temperatures begin to cool. Begin planting spring-flowering bulbs like tulips, hyacinths, crocus and daffodils.
 There is still time to plant radishes and mustard in the fall garden. Use a cold frame device to plant spinach, lettuce and various other cool-season crops for production most of the winter.
 Take tropical water garden plants indoors when water temperatures near 50 degrees. Stop feeding fish at this temperature. Close the water garden for the winter by placing hardy plants in the deeper areas of the pool and cover it with bird netting to catch dropping leaves during the winter months.

Sunday, September 16, 2018 0 comments By: Jack Downer

Reseeding Fescue Lawns in Fall

Reseeding Tall Fescue in Fall
Brian Jervis: Ask a Master Gardener
Sunday, September 16, 2018
Q: It seems like my fescue thinned out this summer. How do I re-seed and when is the best time? DH
A: Fescue is a good choice for areas of your landscape that get some shade. It thrives in spring and winter but struggles with our Oklahoma summers. As a result, most of us need to re-seed our fescue each year to keep a thick, healthy turf.
Cool-season grasses, like fescue, germinate best when the soil temperature is in the 70-degree range. This happens in the spring and fall, but fall is the best time to re-seed as this gives your new fescue the fall, winter and spring to develop a healthy root system. The last half of September through the first half of October usually gives us the soil temperature we need.
Oklahoma is fortunate to have the Oklahoma Mesonet (, which provides us with a wealth of information, including the soil temperature for each county. At this writing, 2-inch soil temperature in Tulsa County is 72 degrees, so this is perfect.
For optimal results, we recommend purchasing seed with a blend of at least three different types of seed rather than a single cultivar. Doing so not only increases your likelihood of success, but also combining grasses tends to reduce the incidence of disease as each type tends to mask the weaknesses of the others.
It is also a good idea to prepare your soil rather than just sprinkle seed on the ground. The upper layer of soil tends to develop a crust so seeds dropped on this hard surface will either blow or wash away before having a chance to germinate. Breaking up the soil can be done with a rake or by perhaps renting a tiller or verticutter for difficult situations.
Seed should be sown evenly with either a rotary or drop spreader and applied at a rate of 3 to 6 pounds per 1,000 square feet when reseeding.
Seeds must have water to germinate, which typically means watering twice a day for a few minutes during the first two to three weeks. The key is to keep the seeds moist. Once the seedlings are 1 to 2 inches tall, you can begin watering less frequently and for longer periods.
Fertilization will also be necessary, and we recommend getting a soil test from the OSU Extension so that you will know exactly which nutrients your soil requires for best results.
One word of caution: If you plan to re-seed this fall, do not use a weed pre-emergent as this will not only work to prevent weeds from growing but will also prevent your new fescue from growing.
We have quite a bit of information at our Diagnostic Center and on our website to help you maintain your new and existing turf: click “Lawn & Garden Help” and then select “Turfgrass” for fact sheets and videos (
Garden tips
  • Watch for fall specials at garden centers and nurseries because fall is a great time for planting many ornamentals. Choose spring-flowering bulbs as soon as available.
  • Fertilize established fescue lawns with 1 pound of actual nitrogen fertilizer per 1,000 square feet now and again in November. Do not fertilize Bermuda or zoysia lawns until next spring. Late fertilization of these warm-season grasses may promote disease.
  • September and early October is garlic-planting time with an aim for harvest in June of next year. There are many varieties from which to choose. OSU suggests German Red, Inchilium Red, Silverskin and Spanish Roja for varieties, which do well in our area.

Sunday, September 2, 2018 0 comments By: Jack Downer

Control of Bagworms on Trees and Shrubs

Control of Bagworms on Trees and Shrubs
Allen Robinson: Ask a Master Gardener
Sunday, September 2, 2018
Q: I am seeing lots of bagworms on my cedar trees and other trees right now. What can I do to get rid of them? Charlotte S., Tulsa
A: Bagworms are common pests on eastern red cedar, other junipers, arbor vitae and sometimes on bald cypress, elms, pines, willows, maples and others. They are unique in that once they form their protective bag later in the summer, insecticides are not helpful. Treatment should begin soon after the eggs hatch in late spring.
The cycle of worm production begins in the spring when eggs that have overwintered in bags hatch. Newly hatched larvae develop small, upright bags while feeding on the plant. Initially, the bags are less than ¼ inch but, when mature, they can reach up to 2 inches in length. Once mature, the larvae close off the bag and fix it to the tree. In mid-summer, the males emerge from bags, fly around and mate with females who never leave the bags. The females lay eggs in the bag and then die. The cycle begins anew in the following spring.
For smaller trees with small infestations, the easiest treatment is to simply pull the bags off and destroy them. This can be done at any time of the year. Be sure to burn them or place them in a well-sealed bag to destroy the bags and their viable eggs. Trees that have heavy infestations yearly should be treated with an insecticide because large numbers can completely defoliate and kill smaller trees.
Insecticide treatment must be done soon after the larvae hatch in late May or early June. No treatment is considered effective once the bag is closed. Be patient as most insecticides will require repeat applications every seven to 10 days for two to three treatments because not all eggs hatch at the same time or there may be migration (wind dispersal of small larvae during June) from other host trees.
There are two relatively safe organic insecticides. The safest is Bacillus thuringiensis kurstaki, or “Bt,” sold as Thuricide and other brands. The good news about this herbicide is that it is not harmful to people, pets or fish. It is a bacterium that infects the bagworm and causes it to starve. It must be sprayed directly on young larvae.
Another biological insecticide derived from a bacterium is Spinosad, a microbial agent that is sold in several brands including Fertilome Borer, Bagworm, Tent Caterpillar and Leaf Miner Spray. Spinosad has contact and systemic activity on target insects. It, too, has low toxicity and a good environmental profile. Be sure to always read all label directions.
Other nonorganic manufactured insecticides are labeled for bagworms and are effective in controlling young worms. However, these insecticides also kill the parasites and predators that normally keep bagworms under control.
So, while the most viable way to rid your trees of bagworms at this time of year is to pick them by hand and destroy them, consider keeping this information handy so that next year the problem can be dealt with in late spring.
Garden tips
  • If your tomatoes are too tall and gangly, now is a good time to prune the top of the plants by as much as ⅓ to ½, depending on the plant. This will stimulate new limb growth and new fruit production after it cools.
  • Reseeding fescue is best done from mid-September through mid-October. If you plan on reseeding, begin scouting for good seed now. Purchase a fescue blend of three or more varieties, with or without Kentucky bluegrass. Read the label on the seed bag. A good blend will have 0.01 percent or less of undesirable “other” crop seeds.
  • In the fall, strawberry plants build up food reserves and form fruit buds for the next year’s crop. They should be fertilized between mid-August and mid-September with a nitrogen fertilizer, such as ammonium sulfate, at a rate of 1½ pounds per 100-foot row. Apply 1 inch of water if no rain is expected.
  • You have all of September to plant cool-season vegetables like spinach, leaf lettuce, mustard and radishes, and until the middle of September to plant rutabagas, Swiss chard, garlic and turnips.
  • The last nitrogen fertilizer application of the year on warm-season grasses should be applied no later than Sept. 15.

Sunday, August 19, 2018 0 comments By: Jack Downer

Don't Miss Out on Fall Vegetable Gardening

Fall Vegetable Gardening is Not to Be Missed
Tom Ingram: Ask a Master Gardener
Sunday, August 19, 2018
Q: I plant a vegetable garden every year in the spring, but I have never tried a fall vegetable garden. What can I plant in a fall garden and when do I plant? SM
A: Oftentimes, fall vegetable gardens get overlooked because we don’t know what to plant, or maybe we are just tired from our spring and summer gardens and ready to call it quits. Either way, growing fresh vegetables can be a year-round activity. And what you may not realize is that some of the best and tastiest vegetables are grown in the fall when warm sunny days and cool humid nights create wonderful growing conditions.
You can divide fall crops into two groups: “tender” and “semi-hardy.” “Tender” means these vegetables will need to reach full maturity and production before the first frost brings their season to an end. “Semi-hardy” means they may continue to grow and be harvested after several frosts. In northeast Oklahoma, Nov. 15 is our average first freeze date. So, unless something unusual happens (in Oklahoma?), you can have fresh vegetables straight from the vine until November and then refrigerate the rest for continued enjoyment.
With the cooler weather we are having (watch it change since I wrote that), now is the perfect time to plant a variety of tender and semi-hardy crops. Tender varieties you could plant now would include bush beans, lima beans, cucumber and squash. Semi-hardy crops would include cabbage and cauliflower (transplants), collards, potatoes (seed potatoes), kale, kohlrabi, lettuce (a little late, but I did anyway), parsnips, radishes, swiss chard and turnips.
Starting in September, you can plant garlic and onions, which are great crops to start in the fall as they grow all winter. If you do this, in late spring next year, you can harvest fresh garlic and onions to last you the entire year (if you grew enough).
Mulch should be an important part of your garden strategy any time of year as mulch helps retain moisture, as well as reduces weeding. In addition, mulch controls soil temperature swings during the day, which helps keep those tender roots happy.
Oftentimes, people contact us wanting to know what type of fertilizer would be best for their situation and how much they should use. There is really no good way to answer this question without testing your soil.
Getting a soil test is not hard. All you need to do is get 15-20 samples of soil from your garden and put them in a bucket. Be sure to dig down about 6 inches with your trowel for these samples. Remove any nonsoil debris and mix up the soil. Then, bring about a sandwich bag’s worth to the extension office. We’ll send it off to Oklahoma State University, and within about 2 weeks, you will know the basic nutrient content of your soil and how to best amend it for optimal results. The test will cost you $10, but in my view, it is likely the best $10 you will ever spend. Happy gardening!
Garden tips
  • Discontinue deadheading roses by mid-August to help initiate winter hardiness.
  • Irrigated warm-season lawns, such as Bermuda and zoysia, can be fertilized once again; apply 1-pound Nitrogen per 1,000 square feet this month. Do not fertilize these grasses after the end of August. Do not fertilize tall fescue lawns in summer; fertilize in late September after it cools and again in November.
  • This time of the year is generally not the best time to prune, but if you have damage to trees and shrubs due to storms, prune out the damage now.