Last updated: Mar 31, 2026
This guide covers tree trimming best practices, local regulations, common tree species, and seasonal considerations specific to Glendale, CA.
Homes along the Verdugo foothills face a different pruning priority than the flatter central city because vegetation management and ladder-fuel reduction matter more near the wildland edge. Narrow driveways, steep grades, and uneven terrain in these neighborhoods complicate traditional pruning plans. When a bucket truck cannot reach a steep slope safely, you must plan for rope access or hand-carry debris in staged steps. This isn't optional-it's a safety necessity to keep limbs away from roofs, chimneys, and power lines during fire season. In Glendale, the terrain forces crews to rework every cut to avoid sliding on loose soil or tipping on a hillside, so expect a slower, more deliberate flow and more frequent, smaller removals rather than one heavy, risky lift.
Foothill neighborhoods are more exposed to hot, dry late-summer conditions, making heavy canopy reduction riskier for tree stress and worker safety. Pruning priorities tilt toward ladder-fuel reduction: remove the "middle story" of branches that allow flames to ladder from grass to shrubs to tree canopy. This means concentrating cuts where needles and small limbs thicken near the base of the canopy, then stepping up to crown thinning only after the inner, highly combustible growth is tanned down. The goal is a defensible buffer rather than a bare skyline. In practice, this demands precise, incremental thinning that preserves essential shade and habitat while interrupting heat transfer and ember capture routes. The approach suits the foothills where ember generation and radiant heat flux can intensify quickly on exposed slopes.
Steep lots in northern Glendale can limit bucket-truck placement and increase the need for rope access, hand-carry debris removal, or staged trimming work. Crews must map every maneuver before cutting, anticipating landing zones for branches and calculating waste routes down slopes without creating new erosion paths. Where possible, cut portions of a limb that pose the greatest risk first, then retreat to safer staging points to finish the remainder. Talk through the sequence with homeowners so you understand which branches come down first and which cuts will require added equipment or extra trips. A well-planned staging area on flatter ground can dramatically reduce on-slope traffic, lowering the chance of slips and wrong cuts that could jeopardize nearby homes or vehicles.
Foothill neighborhoods demand restraint during peak heat and drought windows. The hotter and drier the late-summer period, the more caution is required with heavy canopy reductions. Avoid aggressive crown thinning that creates exposed trunk tissue or unsettled, brittle wood right after a heat spike. Instead, schedule multiple light passes, letting the tree recover between sessions. This staggered approach minimizes stress on the tree, preserves structural integrity, and reduces the likelihood of worker fatigue and missteps on unstable ground. Remember that time-of-day matters: early-morning work in the cool hours reduces heat stress for crews and lowers smoke-inhalation risk for residents.
Defensible pruning in the Verdugo foothills hinges on disciplined debris management. Small limbs and leaves should be hauled away promptly to avoid creating ladder-like fuel on the slope. If access is limited, arrange for controlled, on-site chipping and staged removal that aligns with the property's grades and drive angles. Clear routes must be maintained for fire-safety equipment and emergency access at all times. In Glendale, the rule is clear: every cut should contribute to a safer, more defensible landscape without inviting new hazards from improper disposal or unsecured piles.
Older neighborhoods feature mature London plane, California sycamore, Indian laurel fig, and Chinese elm that outgrew small parkways and tight side yards decades ago. These broad-canopy trees are accustomed to generous space, but in Glendale they now extend over sidewalks, alleys, garages, and neighboring lots. The result is a tree that asks for a pruning plan focused on clearance and weight reduction rather than simple shaping. When sizing up each specimen, start by assessing where branches overhang structures and walkways, and note any embedded weight that could shift as limbs seasonally gain or shed leaves and fruit. Remember that these species tend to have strong secondary branching closer to the trunk; even modest cuts can alter the balance of a limb with substantial mass.
In practice, clearance takes precedence over cosmetic detail. Prioritize ensuring pedestrians can pass beneath without worry, and that branches do not drape over roofs, chimneys, or vehicle ports. Weight reduction is critical where limbs arch toward sidewalks or alleys, especially in heat-driven dry periods when branches become less flexible. Because these trees span multiple parcels, pruning decisions should consider not only the homeowner's yard but the proximity to a neighbor's drive, wall, or fence. When limbs overhang alleys or common spaces, maintain a safe reduction that preserves canopy health while decreasing leverage that could lead to sudden limb drop during wind events or heavy rains. In foothill-adjacent areas, heat exposure and drought stress can dry out limb tissue; thinning should be deliberate, focusing on removing small, crowded branches to improve air movement and light penetration rather than a harsh, large-shearing cut.
Large specimens near historic blocks and established commercial corridors demand more technical rigging because access is constrained by narrow driveways, walls, and overhead obstructions. Begin with a precise site map: which limbs swing toward sidewalks, which head toward rooftops, and where overhangs intersect with utility lines. For overhanging limbs that cannot be reached from the ground without risk, arrange mechanical access that minimizes impact to surrounding structures. When rigging, set up anchor points on stable limbs or trunk sections that can bear the load, and work in small, controlled increments to avoid tainting the tree's natural balance. Keep an eye on limb connectivity; removing large anchors without addressing the secondary branches can leave the tree with new, unpredictable angles that may create future hazards.
First, catalog all branches that overhang sidewalks, driveways, and neighboring properties, marking those that contribute the greatest weight. Second, plan a two-stage reduction: remove small-diameter interior limbs to improve air flow and light, then selectively prune exterior leaders to reduce canopy drip toward structures. Third, in areas where branches cross or rub against walls, cables or strategic thinning can reduce friction and the chance of bark damage. Fourth, confirm that every cut preserves a strong attachment point and does not leave a stub that invites decay. Fifth, revisit after the initial cut cycle to address any new limb movement patterns that may have shifted due to wind or seasonal growth. Finally, schedule future checks to monitor for rubbing, shedding bark, or excessive weight that could necessitate another adjustment before the next dry season.
With older Glendale trees, ongoing maintenance is less about form and more about continued clearance and structural balance. After pruning, observe the tree through the first hot stretch and the first heavy wind period, noting any new contact with sidewalks, roofs, or garage eaves. If branches resume an overbearing angle toward public or private spaces, plan a targeted thinning pass to reestablish safe clearance. For these species, gradual, phased work protects both the tree's vitality and the neighborhood's infrastructure while keeping mature, iconic canopies healthy and resilient.
HouseFace Landscaping
Serving Los Angeles County
5.0 from 37 reviews
Professional Gardening | Garden Design and Maintenance We offer professional gardening services, garden design, green space maintenance, tree and lawn pruning, irrigation system installation, and decoration with ornamental plants. We specialize in sustainable landscaping, creating vertical gardens, and green spaces for homes and businesses. We work with high-quality materials and provide personalized service. Bring your garden to life with us! Contact us for a quote. 🌿✨ Expert gardeners near you. All appointments are made at the client's property, not in the office.
Ultimate Junk Removal
Serving Los Angeles County
4.8 from 44 reviews
We are a professional Junk Removal family business. We take pride in our work. No job is to small or to big for us. You call we haul.
Glendale Tree Services
(747) 221-7470 treeservicesglendale.com
Serving Los Angeles County
5.0 from 4 reviews
Glendale Tree Services provides specialized tree care in Glendale, CA, with expert arborists in tree trimming, tree removal, and emergency services. Established tree service specializing in residential and commercial removal and landscaping projects.
SoCal Landscape & Trees
(626) 563-9026 www.socallandscapeandtrees.com
Serving Los Angeles County
5.0 from 35 reviews
SoCal Landscape and Trees has become a reputable and well-known landscape, tree, routine gardening entity in the Altadena/Pasadena area. We are fast, efficient, and honest. We're here to make your dream come true for your outdoor space. We provide quality work with a great team and we are ready at your service. Our team is up for every job, managing projects with the skill and experience our clients have come to expect.
Top Tree Trimming of Burbank
(747) 285-7693 toptreetrimming.com
Serving Los Angeles County
4.8 from 5 reviews
We recognize that the search for a Burbank Tree Trimming Service can be long and tedious, so we strive to make your experience and search for a reliable Burbank Tree Trimming Service as easy as possible. With an excellent reputation among our customers, our goal is to provide work that meets Burbank’s need for tree trimming and taking the Street Tree Master Plan into consideration. One thing that is certain, when it comes to trimming trees in Burbank, it is better “leafed” in the hands of a professional.
Top Notch Tree Services
(626) 390-8449 www.topnotchtreeservicesinc.net
Serving Los Angeles County
5.0 from 52 reviews
Experience the peak of arboricultural excellence with Top Notch Tree Services, where an unwavering commitment to customer satisfaction drives every project. Our elite team delivers unmatched reliability through specialized services, including precision pruning, hazardous removals, and health-boosting soil restoration. Unlike competitors, we utilize state-of-the-art diagnostic technology and high-quality organic materials to ensure your landscape thrives for generations. Our reputation is built on transparency, safety, and meticulous attention to detail that transforms property aesthetics. Trust our seasoned experts to provide a seamless, high-caliber experience tailored to your unique needs.
JD Tree Service
(424) 488-8342 jdtreeservice.info
Serving Los Angeles County
5.0 from 70 reviews
Welcome! We are a small local business.This is an owner-operated business and we pay special attention to the details of every project to ensure the complete satisfaction of each client. Our goal is to enhance the exterior of your home, raise your property value, and beautify your whole neighborhood. When a tree is not pruned and trim properly not only looks unattractive, it is a liability for your property. Trimming and pruning your trees gives your property a clean look and help your trees grow healthier and strong. Please call or text us 24/7 days a week , and we'll try to get back to you as soon as possible. NO OBLIGATION FREE ESTIMATES. BONDED, FULLY INSURED AND WORK COMP
California Tree Design
(562) 253-9577 www.californiatreedesign.com
Serving Los Angeles County
4.8 from 75 reviews
Established in 2010, California Tree Design is a premier tree service company dedicated to maintaining the beauty and health of trees through customized solutions. We have a team of experts including an ISA certified arborist. We are backed with a CSLB license, Workmans compensation insurance, liability insurance and bonded.We strive for exceptional care and customer satisfaction. We are passionate about preserving trees, providing personalized services like safe removals, pruning techniques and treatments to enhance your property's aesthetic value while promoting the environment's overall well-being. We want to ensure that every property we service whether it's a home, business, or commercial is healthy, safe and beautiful.
Glendale Tree Service Experts
(818) 572-9116 glendaletreecare.com
Serving Los Angeles County
5.0 from 2 reviews
We’re a trusted tree service based in Glendale, CA, specializing in safe tree trimming, pruning, removals, and storm cleanup. From tall palms to aging oaks, we know how to handle trees in our neighborhoods with care and precision. Our crew shows up on time, works safely, and always leaves your property neat when the job is done. As a local business, most of our customers come from referrals, and we’re proud to be known for reliable, honest service. Whether you need a hazardous tree removed or just want your landscape looking sharp, we’re here to help. Serving Glendale, Burbank, Pasadena, and surrounding communities. Call today for a free estimate.
Crescenta Valley Tree Service
Serving Los Angeles County
4.1 from 13 reviews
Crescenta Valley Tree Service is a reliable licensed company, bonded and insured. We provide residential & commercial service the highest quality and professional tree services at affordable prices. We have been providing tree pruning, tree removals, stump removal, stump grinding, palm tree maintenance, palm removals, emergency calls, and fire ordinances compliant services since 1983. Formerly Mike’s tree and spray Inc. serving Altadena, Burbank, Glendale, La Cañada, La Crescenta, Monrovia, Montrose, Pasadena, San Fernando Valley, Shadow Hills, Sunland, Tujunga. Let our qualified experts work on your trees. Give us a call on your tree needs to give you a free estimate.
Pasadena Tree Service
(626) 507-2381 www.pasadenatreesolutions.com
Serving Los Angeles County
4.8 from 20 reviews
The condition of your trees is very important, and we love to keep trees healthy throughout Pasadena, California. You will benefit from a complete landscape management plan tailored to your specific needs and exceeds your expectations, regardless of the season or environment.. Our tree service crew has the knowledge and experience to care for your trees, shrubs, and bushes, resulting in a natural environment that adds curb appeal to all of your properties. With years of training and experience, our arborists will assist in tree removal, pruning, trimming, and stump removal. Professional tree assessments done regularly are essential to keeping your trees and shrubs in good shape.
Alhambra Tree Service
(626) 507-4330 www.alhambratreeservice.com
Serving Los Angeles County
5.0 from 9 reviews
Alhambra Tree Service is a family-owned company with a team of fully licensed, bonded and insured tree care and landscape contractors. For over 20 years, we have served all of Alhambra and the surrounding Los Angeles area for both residential and commercial properties. Our area is especially known for beautiful oak trees and pine trees and we made trimming, pruning, maintaining and removing these trees an industry specialty. Our professional tree care services include tree trimming, tree removal, tree pruning, tree care, tree planting, tree maintenance, tree stump removal, stump grinding, tree fertilization, emergency tree removal, emergency tree services, brush clearing, certified arborists and tree doctors.
California fan palms and Mexican fan palms anchor many Glendale yards with a clean, sculpted silhouette, but they behave very differently from broadleaf shade trees. They shed fronds in long, heavy clusters and are more prone to frond breakage near structures. The typical pruning pattern focuses on removing old or damaged fronds, flower stalks, and seed pods, while preserving a clean crown that supports steady growth. This isn't a one-size-fits-all cut; the palm's crown and trunk health dictate climb angles, rigging needs, and debris handling. In Glendale, you'll notice that palm pruning is scheduled as a distinct service from plane, sycamore, elm, and ficus work.
Tall palms in older neighborhoods and along major corridors can be hard to reach when rear-yard entry is limited or when fronds overhang roofs and detached garages. Access planning matters: evaluate how climbers will reach the crown, where rigging lines will land, and what debris drop zones exist. In foothill properties, steep terrain and tight lot lines require careful staging to avoid damage to fences, irrigation, and pavers. When access is constrained, expect longer job durations and more coordination for equipment and drop zones.
Palm work is often scheduled separately from deciduous pruning because the labor, climbing method, and debris profile differ. Fronds and seed pods generate large, bulky piles that don't break down easily in narrow alleys or along walls. The cleanup focus shifts from thinning and shaping to controlled frond removal, with attention to not scarring the trunk or lightly sanding mature bark. In Glendale, sunsets and heat drive afternoon schedules, so crews plan for cooler hours and steady, deliberate moves to minimize heat stress on climbers and protect property.
Begin with a visual walk-around to identify damaged fronds or signs of pests around the crown. Start at the oldest fronds near the base and work upward, removing fronds at their joint without tearing the sheath. For overhanging fronds, set up rigging to lower segments in controlled drops away from roofs and garages. Remove seed pods and flower stalks when present to reduce windborne debris and seed germination in planters. Finally, inspect the crown for uniformity and balance, trimming only what is necessary to maintain a clean, natural look while preserving tree health.
These tree service companies have been well reviewed working with palms.
California Tree Design
(562) 253-9577 www.californiatreedesign.com
Serving Los Angeles County
4.8 from 75 reviews
Anderson Tree Experts
(818) 248-2254 www.andersontreeexperts.net
Serving Los Angeles County
4.8 from 12 reviews
Mediterranean patterns shape a tight pruning window for many deciduous trees that shed leaves in winter. In this climate, the main pruning window runs from late fall through winter into early spring, before the first serious heat arrives. Homeowners should align pruning tasks with a period when trees are leafless or just beginning to leaf out, which makes structure and branch selection easier and reduces stress on the tree. In foothill properties, where large shade trees anchor hillside yards, taking advantage of this cooler window helps control vigor without triggering rapid regrowth later. Plan major structural cuts, removing crossed limbs, rubbing branches, and weak crotches during this time, so the tree can heal in a cooler, moisture-rich period. This is especially true for street trees near patchwork right-of-way constraints, where clean cuts minimize future conflicts with utilities and sidewalks.
Winter rains soften soils, but on sloped Verdugo foothill properties that soil saturation can delay access for heavy equipment. When soils are saturated, ruts and soil compaction risk increases, particularly on grade changes and near embankments. If a winter storm hits, consider postponing high-impact pruning or equipment-dependent work until soils firm up and access paths dry. Mobility and safety become the priority on hillside yards, where a single slip can jeopardize both crew safety and root stability for mature trees. In periods of intermittent rain, small, targeted pruning that preserves tree health while maintaining clearance around houses and driveways can be scheduled, with larger canopy work postponed until ground conditions are firmer. The goal is to maintain defensible space and access without compromising soil integrity or slope stability.
As temperatures rise, fast-growing urban shade trees experience a spring growth flush that can rapidly increase pruning volume. This means the same tree may go from a routine trim to a substantial shaping or thinning job within weeks. Homeowners should anticipate this surge by scheduling lighter, incremental cuts shortly after buds swell and before heat intensifies, thereby minimizing stress on the tree and reducing the likelihood of regrowth that complicates subsequent seasons. In steeper sites, the flush also shifts access priorities: pruning crews may need to work around active growth zones while managing weight distribution on ladders or lift equipment. Late-summer heat, conversely, reduces crew efficiency and raises stress on recently cut trees, so major cuts should be avoided during that corridor and shaping should be scaled back to maintenance work rather than heavy restructuring.
Across Glendale's varied terrain, a strategic approach is essential. Begin with a deciduous tree inventory and map areas where seasonal access is constrained by slope, soil moisture, or heat risk. Use the winter window for foundational structure work on larger specimens, then time follow-up thinning during the early spring growth surge. Reserve late-summer pruning for light cuts only, focusing on cleanup and hazard reduction rather than major shaping. This sequencing supports safer access, reduces stress on trees during heat, and aligns with the city's mixed urban and hillside landscape.
In foothill districts and hillside neighborhoods, pruning decisions carry more than cosmetic consequences. On private property, routine pruning is often handled without a permit, but every homeowner still bears the responsibility to verify whether a tree is protected by local rules, HOA standards, or site-specific conditions. In Glendale, that means checking both city ordinances and any neighborhood protections that could restrict cutting or removal, especially for mature trees or species with special status. If a tree is near a property line and interacts with public spaces, you may be stepping into rules that are more strict than typical yard work.
Trees that encroach on sidewalks, parkways, alleys, or other public-facing edges can trigger city involvement because the work can affect the public right-of-way. Even minor pruning in these zones should be approached with caution: the city can require permits, and work performed without proper clearance might need rework or could incur penalties. Protecting the integrity of the public edge is not just about keeping sidewalks clear; it's about preserving sightlines, drainage paths, and the safety of pedestrians who rely on clear, well-maintained public spaces.
In hillside and planned residential areas, homeowners may face additional review layers through HOA or neighborhood controls even when the city itself does not require a standard pruning permit. Defensible pruning against wildfire exposure is a common driver in these zones, but HOAs may impose stricter deadlines, setback rules, or tree health standards that impact when and how pruning occurs. The combination of city right-of-way considerations and HOA guidelines can create a multi-step approval process that slows work and increases the risk of noncompliance if not anticipated.
Practical steps to stay compliant start with a careful inventory: identify any trees that overhang public edges, confirm if a tree is on a protected list, and review HOA covenants for pruning, removal, or thinning requirements. Before cutting, contact the Glendale Planning and Building Department or browse the city permit portal to determine whether a permit is needed for the specific tree and location. If the work touches the parkway or sidewalk, plan for coordination with public works to avoid obstructing access or triggering neighborhood complaints. For hillside and foothill lots, anticipate possible HOA review even when city permits aren't required, and prepare documentation that demonstrates careful mitigation of fire risk and maintenance of egress routes. Being proactive can prevent enforcement actions and keep defensible pruning efforts on track.
Hillside streets and older utility layouts in parts of Glendale can place tree canopies close to overhead service lines and poles, especially where mature trees were planted long after the original infrastructure. When a canopy leans toward a line, the risk isn't just brush contact-hot, dry Santa Ana days can push branches against conductors, or citrus and ficus limbs can clog clearance spaces with dense growth. Neighborhoods perched above the street often see these challenges sharpened by irregular street grades, stubborn root systems, and the way ladders must be balanced on uneven sidewalks.
Fast spring growth on large urban trees can quickly reduce line clearance and create repeat trimming needs in neighborhoods with overhead utilities. A single vigorous flush can push into space that seemed adequate last season, especially on trees planted decades ago when spacing was set for smaller growth. Homeowners should anticipate annual or biannual checks in hillside blocks, where slope and wind tend to twist branches in awkward directions. Proactive thinning and selective removal can slow future intrusion but require ongoing attention and coordination with crews who know the terrain.
Service drops to homes on sloped lots can be harder to work around because line angles and elevation changes complicate branch removal. The combination of uphill lines, palm fronds, and narrow access points along steep driveways creates mechanical challenges that standard pruning methods don't always cover. If a limb sits between a pole and a roofline, a careful, staged approach may be necessary to avoid disturbing the drop cables or compromising clearance. In these situations, plan for choreography between pruning visits, sun exposure shifts, and the unique geometry of hillside properties.
These companies have been positively reviewed for their work near utility lines.
Thrifty Tree Service
(818) 996-4577 thriftytreeservice.com
Serving Los Angeles County
4.8 from 100 reviews
Glendale's long dry season and the heat reflected off pavement create additional stress on heavily pruned urban trees, especially in dense built-up neighborhoods where pavement, fences, and tight lot lines trap heat around trunks and root zones. In such settings, trees contend with repeated drought cycles, reduced soil volume, and limited root expansion, all of which amplify the impact of every pruning cut. Effective pruning plans in these blocks take heat load into account, favoring balanced canopies and residual leaf area to sustain moisture loss between storms.
Large ficus, plane, and sycamore trees in compacted parkway or yard conditions may respond poorly to aggressive topping or excessive canopy thinning. In Glendale's narrow streets, surface irrigation and compacted soils restrict root growth, so removing substantial weight from the crown can provoke sighs of stress in these species. Instead, prioritize conservative reductions, targeted thinning to improve light penetration and airflow, and gradual shaping over multiple seasons. Avoid drastic changes that trigger rapid transpiration or wound responses when soil moisture is scarce.
Horticultural timing in this climate must respect the city's scorching afternoons even during mild winters. While it can be tempting to prune year-round, summer cuts in hot inland conditions can compound stress by increasing leaf area that must be cooled through transpiration. When possible, schedule major reductions to late winter or early spring, with light maintenance during the shoulder seasons. If a late-season cut is unavoidable, implement gentle reductions and monitor for signs of leaf scorch, simplified regrowth, or wilting in the hottest periods.
Soil health and root competition become especially relevant in hillside and Verdugo foothill properties where access is limited and soils are often shallow or rocky. In those environments, pruning plans should align with water management strategies and soil amendment practices that improve moisture retention. Mulching, slow-release irrigation, and avoiding soil compaction around trunks help trees cope with sun exposure and airflow restrictions that come with steep terrain and patchy rights-of-way.
In dense urban blocks, palms, ficus, and broad-leaf deciduous trees endure a unique mix of heat, drought, and human activity. Pruning goals should emphasize structural integrity and long-term vigor, preserving strong branch unions in the lower canopy and avoiding excessive removal of interior growth. Regular checks for signs of heat stress-leaf browning along margins, premature leaf drop, and slowed new growth-support timely, measured responses rather than reactive, large-scale cuts.
Typical Glendale trimming costs run about $250 to $1800, with the lower end usually covering smaller ornamental work and the upper end tied to mature shade trees, tall palms, or difficult access. In practice, a routine crown lift or light shaping on a small ornamental tree often lands near the $250-$550 range, while pruning a mature shade tree with multiple trunks or removing deadwood can push toward $800 to $1500, depending on reach and rigging. If a palm requires trimming of fronds, seed pods, or trunk cleanup, expect the price to skew higher as tools and time are needed for clean, safe work.
Prices rise on Verdugo foothill properties where slope, limited truck setup, stair access, or long debris hauls slow production. Steeper sites require more planning, additional manpower, and sometimes a separate bucket or crane setup, which adds cost. Debris haul distance can also influence price, especially when piles need to be moved around tight switchbacks or hauled through narrow driveways.
Jobs also cost more when mature plane, sycamore, ficus, or palm trees overhang roofs, garages, sidewalks, or utility lines and require technical rigging or specialized crews. In these cases, the crew coordinates access from multiple angles, uses rope systems, and ensures protective measures for nearby structures, all of which adds time and expense. On compact lots or hillside properties, access challenges can make each cut slower and less predictable, nudging the total closer to the high end.
Step-by-step planning for hillside trims keeps costs predictable. Start by mapping access routes from the street, noting gate widths, stair counts, and any low-hanging branches that could block equipment. If a plan includes debris hauling, set expectations with the crew about haul distance and staging areas before work begins. For Foothill defensible pruning, prioritize deadwood removal, careful thinning to reduce weight high in the canopy, and keeping branches away from roofs, garages, and power lines. Communicate clearance needs early to avoid rigging changes. Consider staging the work in smaller visits on steep lots, which can be safer and cheaper than one session.