Got Nature? Blog

Purdue Extension forester Lenny Farlee tells you a little about how to identify Silver Maple trees and differentiate them from other species of maple.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
Investing in Indiana Woodlands, The Education Store
Tree Appraisal and the Value of Trees, The Education Store
Forest Improvement Handbook, The Education Store

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Question: We have a customer with an ornamental pear tree that is sprouting shoots throughout their entire front lawn. Do you have any recommendations regarding control, other than removing the tree?

Answer: Hello, and thanks for reaching out with your tree questions. It sounds like the seedlings from ornamental callery pear. For many years, the cultivar Bradford dominated the landscape and was not self-fruiting. But as newer, improved cultivars were introduced to landscapes, they were cross-fruitful with Bradford pears.

So now “volunteer” callery pear trees are seeding themselves in alarming numbers and from their roots as suckers even where they were not planted, helped along by birds. These seedling pears are extremely vigorous and quite precocious, coming into bloom and fruit at a very young age. The Indiana Invasive Species Council has listed this species as highly invasive in Indiana.

Remove seedling trees immediately or keep them mowed very low to prevent flowering and fruiting. Usually, the ordinary broadleaf weed sprays for turf will keep them down. If you have ornamental pear trees in your landscape, keep a close watch for fruit set. If your existing landscape specimens bore fruit this year, you can spray next spring with fruit inhibitor hormone (e.g., ethephon, Florel® fruit inhibitor) to reduce fruit set. Note that timing and thorough coverage is critical. The spray must be applied when plants are in the early stage of full bloom, before fruit sets. Typically, ornamental pear is in bloom for 10 to 14 days. It will be difficult to provide thorough coverage on larger specimens. Be sure to read and follow all label directions.

Below we have several resources that also expands upon the Callery Pear trees.

Resources
Invasive Plant Species: Callery Pear, Video, Purdue Extension
Now is the Time to Identify Callery Pear, Purdue Landscape Report
A “Perfect” Nightmare, Purdue Extension’s Indiana Yard and Garden
What are invasive species and why should I care?, Got Nature? Blog, Purdue FNR Extension
Invasive Species, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel

Lindsey Purcell, Chapter Administrator & Master Arborist
Indiana Arborist Association

---

Purdue Landscape Report: Hot, dry summers are not that unusual in the Midwest, but 2020’s hot dry spell started considerably earlier than usual, before summer even officially began! To make it a triple whammy, the hard freeze in early May caused some landscape plants to burn up more stored carbohydrate reserves to produce a second round of foliage.

I’m sure I don’t have to point out that most of Indiana is currently experiencing abnormally hot, dry conditions. Although recent rains have brought relief to some areas, any respite is sure to be temporary. Seasonal thunderstorms may deluge some landscapes with water while other areas, even those close by, may stay fairly dry. Much of the area has experienced highs in the upper 80’s to over 90º F over the past month.

Leaf scorch on trees and shrubs, appearing as a browning along the edges of the leaves, is very common in dry summers. While minor cases of leaf scorch are not very harmful, prolonged lack of moisture can spell disaster for landscape plants.

Young and newly established plants are most susceptible to the dry conditions, but even established plants may reach a critical point during prolonged drought. If the heat and drought continue this summer, branch dieback, combined with eventual root death, will make plants more susceptible to winter injury. Plants that were already under stress from other factors may succumb to severely dry soils.

The intense heat makes it difficult for plants to keep up with water and cooling requirements, even in areas where moisture is adequate. One of the ways that plants cool themselves is through transpiration, which allows water to evaporate from the foliage. Plant leaves have pores called stomata that can open and close to allow water vapor and gas exchange with the environment. During extreme heat and/or drought, stomata will nearly close, thus reducing transpiration and exchange of carbon dioxide and oxygen. The end result is seen as wilting foliage and leaf scorch. But not so obvious is that reduced water uptake and gas exchange also leads to reduced production of carbohydrates through photosynthesis and reduced uptake of soil nutrients, having longer term impact on plant health.

There is still plenty of summer yet to get through to see the further challenges ahead. Meanwhile, we can mitigate some of the stress by watering landscape plants as needed where feasible.

Resources
US Drought Monitor
Indiana – Purdue Rural Emergency Preparedness, Purdue Extension website
In Times of Drought, Indiana Yard and Garden, Purdue Consumer Horticulture
Drought? Don’t Forget the Trees, The Education Store, Purdue Extension resource center
Turfgrass Disease Profiles: Summer Patch, The Education Store
Iron Chlorosis of Trees and Shrubs, The Education Store

Rosie Lerner, Extension Consumer Horticulturist
Purdue University Department of Horticulture and Landscape Architecture

---

Welcome to the Nature of Teaching Professional Development Webinar Series: Ecotoxicology Part 1. This webinar shared by Rod Williams, a professor and extension wildlife specialist with Purdue University Extension, and Jason Hoverman, an associate professor at Purdue University and a co-author on the unit on ecotoxicology, discusses the principles of ecotoxicology, contaminants, and threats to the freshwater ecosystems.

This webinar shares the resources teachers, and K-12 leaders, need to teach students about ecotoxicology. This state standard curriculum includes free downloads of posters, photos, charts, data sheets, and fun activities along with the opportunity to receive a Certificate of Completion. 

Resources
The Nature of Teaching: Ecotoxicology and Environmental Health, The Education Store, Purdue Extension’s resource center
Benefits of Connecting with Nature, The Education Store
The Nature of Teaching: Disease Ecology, The Education Store
Resourceful Animal Relationships, The Education Store
The Nature of Teaching, YouTube Channel
Nature of Teaching, Website

Rod Williams, Professor of Wildlife Science
Purdue University Department of Forestry and Natural Resources

Jason Hoverman, Associate Professor Vertebrate Ecology
Purdue University Department of Forestry and Natural Resources

---

Join Purdue Extension forester Lenny Farlee as he introduces you to the Bald Cypress in the video below, one of two deciduous conifers in Indiana.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
Indiana Department of Natural Resources – Division of Forestry, District Foresters 
Forest Improvement Handbook, The Education Store, Purdue Extension resource center
Tree Appraisal and the Value of Trees, The Education Store
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Purdue Landscape Report: Slime flux (also known as wet wood) is a dark, foul-smelling and unsightly seepage of sap from tree trunks (fig. 1). The disease is not usually a serious problem but the appearance can be alarming. Slime flux is caused by common surface-inhabiting bacteria or yeast fungi that enter the trunk through wounds associated with improper pruning, stem breakage, injections, cracks from freeze injury or weak limb crotches. The bacteria and yeast may live on sap nutrients within injured trees for many years without any outward evidence.

Symptoms
The main symptom is the appearance of the dark sap oozing on the trunk exterior which happens when gasses produced by growth of the bacteria and yeast cause the internal pressure of the sap to become high enough to force the sap out through cracks in the bark. The dark streaks usually turn light gray or white upon drying. Oozing sap may be frothy and white at the point of exit. Airborne bacteria, yeasts, and fungi often colonize the wet oozing material, which ferments and releases a foul odor. Slime flux may delay wound healing (callus formation).

Slime flux is extremely common on mature elms (fig 2), oak (fig 3) and mulberry; and is seen less frequently on maples (fig 4), paper birch, sycamore, and walnut.

Prevention
There is no control or treatment for slime flux. Inserting a drain tube into the tree to relieve pressure and drain infected sap was once an accepted treatment, but is no longer recommended and may do more harm than good. Boring holes in affected trees causes internal spread of the bacteria within the tree and may allow entry of wood decay fungi.

To reduce the chances of susceptible trees developing wet wood avoid unnecessary wounding of the trunk and branches. Proper pruning techniques, HO-4-W, will allow branches to heal more rapidly. Make sure susceptible trees receive good general care; including irrigation when needed and mulch to conserve moisture and keep mowers away from the trunk. Avoid excess traffic in tree root zone to prevent soil compaction and root injury.

The first and most important step for managing a tree disease is to accurately diagnose the problem. The best approach to diagnosis of tree problems is to start by submitting photos of the tree via the digital upload tool on the Purdue Pest & Diagnostic Lab (PPDL) website. In the case of slime flux it is impractical to collect the type of physical sample needed for confirmation so photos are the best alternative.

References
Sinclair, W. A. and H. H. Lyon. 2005. Diseases of trees and shrubs. Cornell University Press, Ithaca, NY. 660 pp.
Stipes, R. J. and Campana, R. J. (eds.) 1981. Compendium of Elm Diseases. APS Press, St. Paul, MN.

Resources
Diseases in Hardwood Tree Plantings , The Education Store, Purdue Extension’s resource center
Iron Chlorosis of Trees and Shrubs, The Education Store
Surface Root Syndrome, The Education Store

Tom C Creswell, Clinical Engagement Professor – Plant & Pest Diagnostic Laboratory
Purdue University Department of Botany and Plant Pathology

Lindsey Purcell, Chapter Executive Director
Indiana Arborist Association

---

Purdue extension forester Lenny Farlee introduces the red maple, a native tree to Indiana, known for its red to maroon foliage.

If you have any questions regarding trees, forests, wildlife, wood products or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Resources
ID That Tree, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
A Woodland Management Moment, Playlist, Purdue Extension – Forestry and Natural Resources Youtube Channel
Investing in Indiana Woodlands, The Education Store
Tree Appraisal and the Value of Trees, The Education Store
Forest Improvement Handbook, The Education Store

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

This webinar titled “Tree Selection for the Landscape” by FNR Urban Forestry Specialist Lindsey Purcell talks about the tree selection process including the benefits of trees, urban tree planting, purpose for planting, environmental considerations, proper placement and utility considerations, along with many shared resources.

Please visit the Tree Selection for the Landscape Survey after you watch the video so we can learn more about you and feel free to share your suggestions for future topics.

Resources
Tree Appraisal and the Value of Trees, The Education Store, Purdue Extension resource center
Tree Selection for the “Un-natural” Environment, The Education Store
Tree Pruning Essentials, Video & Document
Tree Pruning: What Do Trees Think?, The Education Store
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Installation Process and Practices, The Education Store
Tree Planting Part 1: Choosing a Tree, The Education Store
Tree Planting Part 2: Planting Your Tree, The Education Store
Planting Problems: Planting Too Deep, Video, Purdue Extension – Forestry and Natural Resources Youtube Channel

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources

---

If you missed the LIVE Q&A about invasive plant species from June 4, 2020, no worries. Now you can view the archived video on our Purdue Extension-FNR YouTube Channel with Lenny Farlee, sustaining hardwood extension specialist, and Liz Jackson, extension specialist with Walnut Council and Indiana Forestry Woodland Owners’ Association (IFWOA), discussing invasive plant species, how to identify them, reporting and controlling techniques.

Here are the resources that were talked about in the video as it will help guide you as you identify invasives.

Resources
Help Stop Invasive Species with PlayCleanGo
Best management practices – Top 10 list (pdf)
Great Lakes Early Detection Network – Download the app at Apple App Store
Eddmaps website – A good place to see mapping and keep track of your reports and overall reports by species or location.
Call DEPP 1-866-NOEXOTIC or email depp@dnr.in.gov
Indiana Native Plant Society – Natives to replace invasives
Alternative Option for Invasive Landscape Plants (pdf)
A Guide to the Regulated Terrestrial Plant Species” (pdf)
Calendar of control- seasonality to treatment (pdf)
County CISMA groups, SICiM website
Work assistance- Contractor list, SICiM website
CISMA Virtual Conference in August – Learn about the impact of invasives, importance of native species, a bit about how to control, SICiM website
Midwest Invasive Plant Network Control Database provides an outline and efficacy rating for control techniques for many common invasive plant species.
Grow Indiana Natives Certification Program – Learn about substitutes for invasive species, Indiana Native Plants Society
Report Invasive
Indiana Invasive Species Council is an excellent doorway site to invasive species information for the state
Contact your local NRCS office for EQIP Brush Control practice, tree planting and habitat development practices, Natural Resources Conservation Service Indiana
Woodland Management Moment – Garlic Mustard, Video, Purdue Extension – Forestry and Natural Resources Youtube Channel
Woodland Management Moment: Asian Bush Honeysuckle, Video, Purdue Extension – Forestry and Natural Resources Facebook Page

Elizabeth Jackson, with Manager Walnut Council/IN Forestry Woodland Owners’ Association (IFWOA) & Engagement Specialist
Purdue University Department of Forestry and Natural Resources

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources

---

Purdue urban forester Lindsey Purcell shares tips for tree pruning for the landscape, including knowing why you are pruning, how to prune and how to help the tree heal properly.

Please visit the Tree Pruning for the Landscape Survey after you watch the video so we can learn more about you and feel free to share your suggestions for future topics.

Resources

Tree Pruning Essentials, Video & Document
Tree Appraisal and the Value of Trees, The Education Store, Purdue Extension resource center
Tree Pruning: What Do Trees Think?, The Education Store
Mechanical Damage to Trees: Mowing and Maintenance Equipment, The Education Store
Tree Installation Process and Practices, The Education Store
Tree Planting Part 1: Choosing a Tree, The Education Store
Tree Planting Part 2: Planting Your Tree, The Education Store
Planting Problems: Planting Too Deep, Video, Purdue Extension – Forestry and Natural Resources Youtube Channel

Lindsey Purcell, Urban Forestry Specialist
Purdue University, Department of Forestry and Natural Resources

---