Christmas Tree Scouting Report: March 19, 2026

This past week, March 12 to 18, brought some truly wild weather across Pennsylvania, with many areas experiencing temperatures in the 70s and even low 80s one day, followed by snow and freezing conditions shortly after. These rapid swings have created very uneven field conditions across the state.

Across the southeast and southcentral regions, warm stretches pushed soil temperatures upward and initiated early bud swelling on several evergreen species, particularly on south-facing slopes and lower elevation sites.

In the central region, conditions have been more variable, with moderate warming followed by cooldowns. Soil temperatures are beginning to respond, and early signs of bud movement may be present but remain inconsistent.

The northeast and northwest regions have remained cooler overall, with lingering snow cover in some areas and slower soil thaw. Buds in these regions are largely still tight, with minimal visible development.

Moisture conditions have also varied widely. Rainfall improved surface soil moisture in some areas, while others are still influenced by snow cover and ongoing freeze-thaw cycles. Snow cover has played a dual role, helping insulate soils while also increasing light reflection and exposure on foliage.

As a result, growers should expect a staggered start to the season, with more advanced development in southern regions and delayed activity in northern and higher elevation sites. Continued temperature swings will likely contribute to uneven progression in bud development across Pennsylvania.

Pest Information

Mites

Spruce spider mites overwinter primarily as eggs laid the previous fall, so early-season scouting should focus on locating these overwintering stages. The eggs are extremely small, about the size of a grain of dust, and appear reddish brown to dark red in color. They are typically attached to needles or found at the base of needles along twigs. Growers will often find them concentrated on older interior foliage and lower branches, and they may also be clustered near bud scales or at the base of needles. As temperatures begin to warm in early to mid spring and approximately 50 to 100 growing degree days base 50°F accumulate, these eggs begin to hatch. During cool springs, hatch can occur gradually over several weeks, allowing mite populations to build before summer heat naturally slows their development. Finding overwintering eggs early helps identify potential hotspots before feeding damage is visible and allows growers to prioritize blocks that may need closer monitoring. When scouting, use a 10 to 20x hand lens to carefully inspect needles and twigs for eggs. If significant numbers are present, begin weekly monitoring using the white paper tap test as temperatures rise to detect the first active mites. Paying attention to the overwintering egg stage in early spring can give growers an early indication of potential mite pressure later in the season.

Fertilization practices can also influence mite pressure. Excessive nitrogen fertilization can encourage lush, succulent growth that may favor increases in mite populations. Early spring fertilizer applications, particularly those high in nitrogen, can sometimes contribute to conditions that support faster mite population development if mites are already present. Maintaining balanced fertility based on soil and foliar test recommendations and avoiding unnecessary early-season nitrogen applications can help reduce this risk. Paying attention to the overwintering egg stage in early spring, along with thoughtful fertility management, can give growers an early indication of potential mite pressure later in the season.

For spruce spider mite management in Christmas trees, selecting the right active ingredient early in the season can improve control and extend the period of suppression. Materials that target eggs or both eggs and immature stages are particularly valuable when applied early because they help prevent populations from building during the cool spring period when mites are most active. Several active ingredients registered for Christmas tree production in Pennsylvania provide these advantages.

Growth regulator miticides such as hexythiazox, etoxazole, and clofentezine are often well-suited for early season applications. These products primarily target eggs and immature stages and can provide longer residual control when applied as mite populations begin to develop. Because they prevent eggs from hatching or immature mites from developing into adults, they help suppress future generations and can provide extended population suppression when applied early.

Spirodiclofen is another option that can provide longer-lasting suppression. It affects multiple immature stages and can help slow population development over time. This type of product is often useful when mites are beginning to build but populations are still relatively low.

Contact miticides such as bifenazate or combinations like bifenazate plus abamectin provide strong knockdown of active mites and are useful when populations are already present and feeding. These materials typically provide several weeks of control but may not have the same level of egg activity as growth regulator products.

Abamectin and related miticides such as fenazaquin and fenpyroximate also provide strong activity on mobile mite stages and can help quickly reduce populations. These products are often used when mites are actively feeding and visible during scouting.

When planning a control program, applying a material with ovicidal (kills the egg stage of a pest) or growth regulator activity early in the season can provide longer suppression. Ovicidal product works by preventing mite eggs from hatching, which helps stop the next generation before it becomes active and begins feeding on needles. Miticide/acaracides say on the label if or if not they have activity on eggs and some say they do have ovicide activity, but not on overwintering eggs, so target when eggs are hatching. Many labels are different, especially between active ingredients. If populations are already present, a contact miticide may be needed first to reduce numbers. Rotating products with different modes of action is important to help prevent resistance and maintain long term effectiveness of miticides used in Christmas tree production. Always consult and follow the pesticide label for rates, timing, and application instructions.

Winter Desiccation

As we are getting back into the fields, we have observed winter burn on Norway Spruce, Fraser, and Nordmann fir so far, though additional species and varieties may also be affected. This is a form of dehydration injury caused by winter sun, wind, and frozen soils, limiting water uptake. Damage is most noticeable on south and west exposures, with needles turning brown, yellow, or reddish in late winter and early spring.

This season, conditions across much of the state contributed to injury in multiple ways. Periods of heavy snow cover helped insulate soils and protect roots, but also increased light reflection onto foliage. Snow can act like a mirror, intensifying sunlight exposure on needles, especially on south and west-facing sides. In contrast, areas with inconsistent snow cover experienced deeper soil freezing, further limiting water uptake. Both scenarios can lead to increased needle desiccation.

While injury can appear severe, in many cases it is limited to the needles and buds remain viable. This is an important distinction, as trees with live buds are capable of pushing new growth and recovering as the season progresses.

At this time, avoid immediate pruning. Wait until trees break dormancy and begin to flush so you can accurately assess which tissue is truly dead. Use the scratch test on suspect branches. Green tissue under the bark indicates the branch is still alive, while brown and brittle tissue should be pruned back to live wood.

Water availability will be critical moving into spring. Adequate soil moisture from consistent spring rains will help support recovery, and irrigation can be beneficial where available. Trees affected by winter burn are coming out of winter in a dehydrated state and will respond to improved moisture conditions. Fertilization should be based on soil test results to ensure balanced nutrition and avoid unnecessary inputs.

Overall, patience is key. If buds remain alive, many trees will recover and grow through the damage over time.

Nursery News

Many Christmas tree growers across the region are also producing a range of other plant material, particularly in field-grown and B&B systems. This section highlights observations and management considerations for those crops based on what is actively being scouted and reported by growers.

Growers are encouraged to share observations on other evergreen or nursery species seen in the field. This space focuses on timely "hot topics" as they arise rather than serving as a full scouting report for those crops. The goal is to provide practical, real-time insight tied to what is happening across evergreen production systems.

Nellie R. Stevens holly are showing symptoms related primarily to winter exposure rather than snow load injury. Many plants are exhibiting what is referred to as foliage fracturing, a term used to describe the loss or shedding of leaves following winter stress. This is typically the result of desiccation caused by cold winds, sun exposure, and limited water uptake during periods of frozen soil.

A key observation this season is the contrast within individual plants. Foliage that remained under consistent snow cover is often green and intact, while exposed portions are showing significant leaf drop, bronzing, or thinning. This highlights the protective role snow can play in buffering plants from harsh winter conditions and reducing moisture loss.

Management will vary depending on severity. For light to moderate damage, allow plants to push new growth before making selective pruning cuts back to live tissue. In cases of more severe damage, growers may choose to shear plants back to re-establish form and density. When heavy shearing is required, expect a recovery period of approximately 18 to 24 months to regain marketable quality.

Damage can impact grading and sale timing, particularly in B&B production, where fullness and uniformity are critical. Plants with moderate to severe foliage loss may need to be held and regrown to meet grade standards, potentially delaying marketability by one or more growing seasons.

Maintaining adequate soil moisture through spring, whether from consistent rainfall or irrigation where available, will support recovery and help plants push new foliage to replace what was lost.

Next Report

The next scouting report will be available on March 26th, 2026. Reminder, please submit observations anytime prior to Tuesday, March 24, 2026, by noon to Kelly Piccioni at keg200@psu.edu to be included in the next report. As a reminder, you may also call into the hotline weekly for updates: 1-800-PENN-IPM (1-800-736-6476) option 5.