3 (lowest strength, not pretty). 2 Dimension Lumber characteristics. Pressure-Treated Southern Pine ), how wood is used also comes down to whether or not it's pressure treated. The cores are then dried and ground for the purpose of analyzing the dust by x-ray, titration or gas chromatography methods. maple, oak, birch, etc. hbbd``b`i@i`}{" s@BHpE ^ !RHp@00 30 .
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Best appearance (compared to Standard) High-quality lumber Smaller and fewer knots Standard Grade: Use when a rustic appearance is desired. Grademarks | SPIB | Southern Pine Inspection Bureau Most of this new treated lumber looks untreated as compared to the old green stuff, I did learn that they add color to some of it to try and make it look more like treated. Each charge is tallied as to the specific Production Category that will be used to determine the level of sampling to be performed in the plants treated wood inventory. Those stacks also include some No. Pressure treated lumber has been infused with preservatives to prevent rot and insect damage. Decking materials such as 26 and 5/46 frequently are of better-looking #1 and #2 lumber. Borates are sodium salts used in water-based pressure treatment solutions. All four longitudinal faces must be free of pith and/or heartwood. Spi-1 and Spi-B control the expression of the Grap2 gene in B cells The appearance doesnt affect the structural grade, it just is superficially more appealing. endstream
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The SPIB publishes grading rules under which 95% of the production of the entire industry is classified and sold and maintains an extensive training program in a classroom setting, on the web, and at the mills. #2 Prime grade southern yellow pine. (See Wood Code, below). This process is required through the plants Internal Quality Control (IQC) for all treated lumber products to be represented as meeting an applicable standard. Generally clear, although a. The molecular changes in wood composition have a result of dimensional stabilization, protection against rot and wither, and as a result, expanded use opportunities. However, they make an ideal solution for use in arid or dry locations. WWPA offers a heat treatment certification program for mills to stamp qualifying lumber with the KD - HT mark. By submitting your email, you agree to our, 5 Easy Ways to Remove Scratches from a Glass Window, Build It | Shaker End Table with Char Miller-King, Do Not Sell or Share My Personal Information. The charge is considered conforming if each component meets the minimum required retention AND the total, combined minimum retention is met. 139 0 obj
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SPIB performs these functions through the accreditation of the American Lumber Standard Committee (ALSC) as appointed by the Department of Commerce. It is the material of choice with both professionals and do-it-yourselfers for projects exposed to the rigors of weather, hot, humid climates, decay, and termites. I only use ground contact when the wood is actually touching the ground. ACQ is another environmentally safe preservative composed of soluble copper and either quaternary ammonium alkyl or substitute compounds. Treated wood will shrink as it dries and expand when wet and may acquire surface checks and cracks over time. SPIB is subject to continual review by IAS to ensure that the laboratory and agency records remain in compliance. We think it is only appropriate to attempt to describe these grades for your reference to help you better understand what you currently stock and what is additionally available to you and your customers. Recommended for general construction purposes where appearance is not a controlling factor. Fax: (850) 434-1290. AC2 2 x 6 #2 Prime Ground Contact Tongue and Groove Treated - Menards Southern yellow pine (SYP) is very strong and is common in the eastern U.S. A mixture of spruce, pine, and fir (SPF) dominate much of the northern U.S. and eastern and central Canada and isnt as strong as SYP. See SPIB Special Product Rules for design values, Appearance is same as B&B Finish for thicknesses of 4" and less. Email: cspsales@canfor.com. A quick depressurization cycle then removes any excess from the wood before it is removed from the treatment cylinder. Framing lumber, unlike money, does grow on trees, so theres always the chance it will have some natural defect, such as a large knot or a long split, that can reduce its overall strength. Douglas fir, fir, and hemlock dominate in the western U.S. and Canada, with Douglas fir ranking the strongest of the commonly milled and treated softwoods, while the fir and hemlock are slightly stronger than SPF. Follow the link here to complete our Treated Division and Laboratory Customer Satisfaction Survey. Construction grade is #1 and Standard is #2. r Wood treated with water-based preservatives for saltwater immersion has significantly higher retention levels than other types and categories. However, enough gets into the wood to provide a shell of protection that cant be matched with a brush. Design values only apply to utility lumber that is 4 wide. The ALSC also accredits third-party agencies, like SPIB, to inspect treating plants that produce treated lumber products with preservative systems listed in the American Wood Protection Association (AWPA) Book of Standards (BOS). Modern science has developed preservative treatments that are odorless and colorless, and leave the wood paintable and dry to the touch. The unique cellular structure of Southern Pine permits deep and uniform penetration of preservatives, rendering the wood useless as a food source for fungi, termites and micro-organisms. Any lumber experts out there that can confirm KD HT is ok for a new deck? Grades of Lumber - Culpeper Wood Preservers Just to second what rjniles just said, the HD guy couldn't be more wrong (imagine that). 7nX"a*C[3Dj8[n7;c}W6ynCK2AC?jP0zD'm)a7"tq~eikT):ozU*9Ry"EEy*x|r+Q/!P2GD[0iNvXv4HS-ljs2$r%M$-gi"H"3J2!&IjHnVo " 3Xi^!gc18,WxFWF2O0eMu ~e{lcoJxK]a|rJaxWFX1' g%|M'kL&^JgY9#%T;RnrIwdmdx:rNY%KDn1s,eD8WNjSgvb5OPYn0?
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Z,4zl,RrIl@%<6dWoLMf6Y6J6agH Advances in preservative treatments, environmental management and sustainable forestry practices make treated wood an ecologically sound building material. Its moisture content of 19 percent or more makes it inexpensive, but it can move unpredictably as it shrinks and dries. Its appearance ranking is 80% or better clear of defects. 2 grade lumber, commonly referred to as "#2 & Btr" is used where high design values are required and high appearance in not a factor. It has anti fungal properties along with a host of other positive features. For demanding applications, such as interior load-bearing walls, hell pay extra for these stronger grades. The American Wood Protection Association (AWPA) sets the standards for the retention level required for the different chemical preservative compositions for specific types of use. Recommended for general framing purposes. All rights reserved. While all species are graded at the same four levels of strength and appearance, they are not equally strong. Lumber with more checks, splits, wane, well-spaced larger knots and holes, and a grain slope of 1 in 4 are stamped #3 or construction grade. Tel: 843-236-9399. Excellent for painting or natural finish where requirements are less exacting. Although there may appear to be many differences in what options to use for your next project, there may be more similarities than you know. In preparation for treatment, like lumber products are grouped together onto moving trams and placed into a large cylinder for treatment of the charge. Lumber Grade Stamps - InterNACHI - International Association of May 26, 2016. Green Building Material . The preservatives provide protection against rot, insects, mold, and fungi, so the wood lasts longer. Grade Descriptions - Southern Pine As I understand it, the grade refers to the number of knots in a given length. Fax: (850) 434-1290. Wood Packaging Material (WPM). PDF Pressure-treated Southern Yellow Pine MCA can be used inside or out, above ground, in-ground, or in fresh-water contact residential areas. www.strongtie.com/products/ptwoodfaqs.html, FAQ: Pressure-Treated Wood | Simpson Strong-Tie. #2: When appearance is of moderate concern, this grade will contain moderate size knots and can have a considerable amount of wane. Commonly used for joists, trusses, and other load-bearing applications. Recommended where appearance and strength are a consideration. has the outer 0-0.6 removed while lumber thicker than 2 (44, 46, 66) has the outer 0-1.0 removed for assay. Lumber, posts, and ties range from 8 to 16 in length, although longer may be ordered. When pressure treated it is resistant to decay and termites. The size, location, and the number of knots and other defects, and the slope of the wood grain affect the structural strength of lumber. Pressure treatment doesnt make the wood stronger or weaker, just more resistant to insect and moisture damage. To qualify for a SPIB grade-marking license, a mill must have verified credentials in the manufacturing, seasoning, and grading of Southern Pine lumber. Termawood vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C without ANY chemical additives. An easy way to identify the right framing lumber for your needs. ? In ancient times the Greeks used olive oil, the Romans tar, and others used pitch or lye. The molecular changes in wood composition result in unique features: Not all PT is rated for ground contact. But using bigger joists of a cheaper species might save you money without loss of strength. KD HT lumber vs PT lumber for deck - InterNACHI Forum Listed spans are for wet-service conditions, pressure-treated Southern Pine floor/deck joists, MC > 19%. It should be noted, #2 & BTR does not mean #1. The best pressure treated wood for decks is Select, #1 or #2 grade wood. MCA is an environmentally friendly water-based preservative considered safe for humans and animals and is an alternative to CCA. Used for such purposes as studding, blocking, plates, bracing and rafters. Construction grade commonly refers to #1 grade lumber. The grade mark can include "1W" or "2W" if visually graded to the wane requirements for No.1 or No.2 dimension lumber, respectively. Those stacks also include some No. What's this lumber stamp mean? - Fine Homebuilding '\ & Ls30+X61j\e(gV]]M(q9qs)loyM A Production Category is defined as a given preservative, specie and retention combination. The kinds of softwood available in different geographic regions often determine what species is available for pressure treatment. In appearance, it is at least 57% clear of defects. The stamp identifies the wood species, grade, moisture content, inspection organization, and the mill it came from. Larger sizes conform to Dense Structural 72 Structural Lumber except for dense grain requirement. Has a better appearance than No.1 Dense Dimension Lumber because of additional restrictions on firm red heart, pith, knots and wane. Today, pressure treated lumber for residential use is commonly pine, spruce, or fir that has been immersed in a water-based chemical bath of preservatives. *Load duration factors greater than 1.6 shall not apply to structural members pressure-treated with water-borne . The stapled on label will have w/CE to indicate with color enhancement, she is correct. Standards Revised The 2016 Book of Standards published by the American Wood Protection Association(AWPA) includes revisions to treated wood standards: Ground Contact-treated wood is now required when installed less than 6 off the ground; when it is wetted on a frequent and recurring basis; for joists and beams that are difficult to maintain, repair or replace and are critical to the performance and safety of the structure; when used in tropical climates. Good, serviceable sheathing; usable for many economical applications without waste. Some lumber is also treated for fire protection and used throughout different areas of residential, commercial, and industrial construction. As a result, we have more grades available to our customers now than at any other time in the history of our company. UC3B or UC4A are best for ground contact use. End-glued, face-glued, and edge-glued Southern Pine in glued assemblies, including stress-rated grades of finger-jointed 2" Dimension Lumber. She said that some of the new PT looks so much like untreated they have to add a color enhancer to it. H\n0l/$x\$-"-! The stamps on lumber do not always include everything, the PT data is usually just on one of those plastic tags stapled on the end of the board which gets cut off or removed. Tags: None The Duke CCA Pressure-Treated Wood Wood-constructed homes, roof shakes and shingles, exterior decks, and children's play equipment that were built before 2004 and not made of cedar or redwood were likely constructed using wood that was pressure-treated with CCA, or chromated copper arsenate. Pressure treatment of lumber has come a long way in the past 100 years. However, treated lumber may be kiln-dried or wet and will shrink, cup, and warp as it dries. Generally sound and tight-knotted. Lumber must be stamped for strength by a trained inspector and identified with a legitimate stamp. WestWood Heat Treated Lumber Production Corporation is unique technology that uses heat treatment instead of chemicals for timber processing to significantly improve various characteristics of wood. Economical, serviceable grade for natural or painted finish. Southern Pine's ease of treatability has made it the preferred species when pressure treatment with wood preservatives is required. r Allows well-spaced knots of any quality. Tel: 251-457-6872. Recommended where high strength, stiffness and good appearance are desired. For appearance, it must be 29% clear of defects. See Table 2 or SPIB Grading Rules for design values. This Old House general contractor Tom Silva usually buys stacks of No. By the end of the article, youll have a better understanding of what different pressure treatments mean, and how to select the grade and type for the use you intend. Final Price $ 27 40. each. Stud is a fifth designation, meaning its good for a load-bearing wall. OK then thanks. It needs to be treated every 2 to 3 years (depending on the environment) to protect it from moisture damage. This website is presented by SFPA members, including: 2023 Southern Forest Products Association. The lumber has the structural strength it is graded with but has fewer blemishes or knots, so a better appearance. A number that identifies the mill where the lumber was produced. #2 or #1 is the quality. CCA is a mixture of chromium, copper, and arsenic that turns wood green. For a better experience, please enable JavaScript in your browser before proceeding. The accredited inspection agency, manufacturer, and plant are also commonly on the label but may be available in the bar code. (@ 2=h/jO,,5rB
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While each charge is evaluated on its own merit, it is important to note that overall evaluation of plant performance is done over the most recent 20 samples. The SPIB grade-mark is recognized as a sign of integrity within the industry. Tell us how we're doing! The vacuumed cells more readily absorb the solution for better penetration. Description & Documents #2 prime southern yellow pine with virtually no wane CA-C Above Ground pressure treated exterior wood protected by Ecolife (EL2); a stabilizing formula that repels water keeps boards straighter and looking better longer Ecolife (EL2) provides built-in water repellency that lasts for up to 3 The longer the wood is in the pressure chamber, the greater the content of chemical preservatives forced into and retained in the wood. Similar in appearance to No.1 Dimension Lumber. The ranking goes from Select Structural (highest strength, best appearance) to No. Grade based on No.1 Dimension Lumber except wane and other characteristics that affect appearance are limited. These factors, plus the moisture content at the time of milling, determine the grade assigned. Recommended for same purposes as Construction grade. Pressure treated lumber commonly is end-tagged with an information label before leaving the plant. It is used for all areas of residential construction from load bearing to trim. It has a grain slope of 1 in 12, may have seasoning checks, and tight, well-spaced knots up to 2-1/4 on a 28. Luckily, a more budget-friendly option of pressure treated lumber grades is available. Recommended where appearance and strength are a consideration. I don't think HD carries it. hb```"/VI ealR]2L
7] u~m>^;+g=ll&Cv)!N&%5g~IK1 s Pressure treated to a Ground Contact retention of either ACQ or CA Chemical preservative. 2 lumber, which provides good strength at a reasonable price. As I understand it, the grade refers to the number of knots in a given length. Machine Evaluated Lumber is also required to meet certain visual requirements. Similar in appearance to No.2 Dimension Lumber. How to Read the Stamp - This Old House Copyright 2023 This Old House Ventures, LLC. Follow along as we decode the stamp and show you how to get the most lumber for your money. it would be unsuitable unless it is a naturally resistant wood such as teak or redwood. #1 #2 prime etc deals with the quality of the board. Structurally, an SPF #1 28 can be used to span distances of 14-11. SPIB is committed to assisting our customers meet their treatment goals in the most cost-effective means possible. Dimension stability improves 12-17 times compared to untreated wood Ground contact level treatment (.15 pcf) has more than double the preservative of above ground level treated wood (.07 pcf) Lighter, more natural wood appearance for improved staining qualities. {Vzgil=ecQ*Q\o[lb[9X^gZyzzxzxxxyO`}@}(% m6@93 gx$?yV7`{x"?W@_} s Working with pressure treated lumber is similar to working with untreated planks. Im building a deck and am getting conflicting info on the difference between #1 and #2 PT. Good appearance, but graded primarily for strength and serviceability. MSR Scaffold Plank is available 2"-thick only. WestWood Heat Treated Lumber Production Corporation vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C (450 F) and exclusive of any chemical additives. Walking into a lumberyard or store can be a daunting experience. Heat Treated vs Pressure Treated Wood - Canadian Home Inspection Services This double treated Ground Contact lumber must be used for applications where treated lumber is difficult to maintain, repair or replace. I am finding lots of info about how HT (heat treated lumber) is required for packaging, pallets etc to prevent the spread of some WDO across the world but can not find anything concrete on whether or not it is suitable for a deck. The result of having a unified rating means the end-tag on lumber identifies how well the wood will stand up in different conditions, regardless of the chemical cocktail its been exposed to. Appearance is same as C Finish for thicknesses of 4" and less and widths 12" and less. This approach is intended to consider the big picture trends as opposed to allowing otherwise isolated issues to severely affect plant performance status. I didn't ask but I doubt the deck boards and 2x are ground contact which deals with the amount of preservatives used on the lumber. Pressure treated wood can also be stained or sealed to enhance its color and for added protection. Bruce, I found more info on the heat treated wood. IQC results of treatment for each charge are required to be documented in the plant records to correspond to the individual charge reports. I will try to post-some new treated lumber being sold in the wood depot I go to referd to as BLUE if I am not mistaken. It is a very strong and stiff softwood, and dense too. But not all defects are obvious. 1, No. Pressure treated wood used for in-ground or critical use has a greater retention level than timber used for above or ground contact. Some on this forum think that is a waste of time, but I think it extends the life of the lumber. Preservative Treatment When pressure-treated lumber is required, it should be treated according to appropriate American Wood Protection Association (AWPA) Standards or through the product evaluation process of the International Code Council (ICC) Evaluation Service. The wood is commonly used for light construction or framing where it isnt visible, or for bracing, packaging, and shipping purposes. Many homes have fences, retaining walls, and garden boxes constructed of treated wood, and even the wooden utility poles supplying power and communications are pressure treated. It may have poor drainage and air circulation, or like a sill plate, is difficult to repair or maintain. No.2 Non-Dense No. Gives the trademark or number of the mill of origin. 32524-0915 Georgia-Pacific pressure treated lumber is an economical building material that offers all the benefits of wood, plus built-in resistance to decay and termite damage. Outside building projects and even some damp areas inside require wood that is resistant to moisture damage. Machine Stress Rated (MSR) lumber is evaluated by mechanical stress rating equipment. Box 10915 Pensacola, Fl. Unfortunately, the water-soluble nature makes them susceptible to leaching out in rainy or wet areas, or near standing water. hVmO9 ^TUJk[ The preservatives provide protection against rot, insects, mold, and fungi, so the wood lasts longer. MSR lumber is distinguished from visually stress graded lumber in that each piece is non-destructively tested. The main tree species used in the manufacture of pressure treated lumber are softwoods that regionally predominate in the mill area. Similar to MCA, the treated wood shouldnt be used in contact with food or animal feed. H\Ak0:b
@HZ=8&5FqjfvRut.I/55zb6+]5m&.wgUWm,ZM]nrO=gu${Tu?co2:4 2 kd 19 ht 434 and spib ht 434 it looks like it's kiln dried and heat treated, but is it pressure treated to resist rot? Our next Blog will take the samples to the SPIB laboratory for analysis to determine if retention values are conforming. Mobile, AL. A specific indicator or a specific method is then used to reveal the depth and consistency of preservative penetration. For additional information on the proper handling and storage of pressure-treated Southern Pine materials,click here. "Stud" is a fifth designation, meaning it's good for a load-bearing wall. Application of the product requires pressure treatment by an approved treating process and preservative for marine usage. Dressed to standard dry size prior to machine stress rating, and visually graded to assure that characteristics affecting strength are no more serious than the limiting characteristics for each grade. Top-quality lumber 2x4 through 2x12 are either #2 Prime grade, #2 & Better/Appearance grade or #1 grade. Dont know anything about the HT lumber, but if you are in the west, the PT is still Western Hemlock and looks pretty much the same as before. High utility value where appearance is. Being 80% or more clear of defects, it is often used for cabinetry, furniture, and trim. Lumber is stamped after it is milled and prior to being pressure treated. The treated wood is then taken to the yard to dry naturally or to the drying kilns before shipping to the retailer. Pressure treated wood has many outdoor uses and even is used in some indoor locations, especially where moisture may be a concern. Even if you are on the right track, you will still get run over if you just sit there. Lumber stamped #2 grade is commonly used for framing, lintels, rafters, trusses, joists, beams, and fencing. check out this FAQ web site. It could be HT and then PTd later? @_10ip CzHrGfnl~Frc>fkH 2X [ ^
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High quality with good appearance characteristics. Some mills may then identify it A, B, C, or D for appearance based on how clear or free it is of knots and blemishes. For complete information about types of preservatives, the latest industry standards, product identification and specification guidelines, refer to SFPAs booklet,Pressure-Treated Southern Pine (download in Publications). These values are modified using procedures shown in "Calculating Apparent Reliability of Wood Scaffold Planks," as published by the Journal on Structural Safety, 2 (1984) 47-57, and updated in 1993. r Here is another good link a guy posted over on Ins News Longleaf, shortleaf, loblolly, and slash are some of the native southeastern pines that are classified as SYP. The wood grain has a 1 in 8 slope, and there may be bark edge or wane visible. The recommended type of treated wood for in-ground use is UC4B and UC4C; UC4B has a higher retention level than lower graded types, and UC4C has even more. Locations Products. Protecting wood against rot and insects has been done for centuries. There are different types of treatment and lumber grades for different uses. In most cases, the required depth of penetration is 2.5 or 85% of the available sapwood. vX63t$i"CIdxGFG(bpX@F2@2@pGG1Z@? 43:Gs *
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The dry wood is loaded into a treatment cylinder which is then sealed and depressurized to vacuum as much air as possible from the wood cells. Ultimately, our program provides an economically sound and standardized method of treatment, evaluation, labeling and certification for producers, specifiers and end users of pressure treated wood products. This information will then be combined with previous plant data to determine the plant performance status, as mentioned above. Tough to find decent boards. Twenty cores are taken randomly throughout the charge to measure the depth of preservative penetration in each core. Some wood goes through a machine that incises small cuts into the surfaces for deeper chemical protection. Once on the drip pad, the material will stay until it is dry enough to be moved into the plants treated inventory. As we can find no formal and simple description of all the different grades, we attempt to describe the grades that we currently stock so that you can decide what best fits your need and customer base. UC5A has almost double the weight of chemical protection as UC4C, and UC5B and UC5C both have more than three times the amount found in UC4C. Both DIYers and building professionals will like these garden and outdoor living ideas and plans. Larger sizes conform to Dense Structural 65 Structural Lumber except for dense grain requirement. Recommended for uses where high strength, stiffness and good Species and Sizes Of Pressure Treated Wood, Different Kinds of Softwoods That Are Pressure Treated, Tips for Working with Pressure Treated Wood, Types of Pressure Treated Lumber and Where to Use Them, Sill & bottom plates, damp locations, basement framing, bathrooms, flooring, baseboards, Exterior Above Ground, Coated with Rapid Runoff, Exterior Above Ground, Uncoated or Poor Runoff, Cedar shakes, exterior stairs, joists, beams, decking, railings and fence boards/pickets, any wood within 6 of soil & vegetation, Fence, deck & structural posts, ledgers, retaining walls, garden boxes, any wood within 6 of soil, vegetation, or freshwater, or poor air circulation, As with UC4A plus posts set into the ground, retaining walls, wood foundations & supports, freshwater contact, saltwater spray, garden & utility posts, Pilings or wood in direct installation in soil, gravel, concrete, freshwater, or extreme weather exposure, Contact & immersion in cold ocean waters north of Long Island & San Francisco, docks, piers, wharves, shore walls, boardwalks, & buildings, Contact & immersion in warmer ocean waters south of San Francisco and Long Island, and similar to UC5A, Contact & immersion in warm Gulf Coast waters & south of Georgia, and similar to UC5A, Interior construction, no ground or moisture contact, fire partition walls, kitchens, hallway & stairwell framing, Exterior construction, exposure to weather but not ground contact, porches, exterior stairs, window treatments, Tight and well-spaced, and no larger than 2-3/4 on a 28, Well-spaced and no larger than 3-1/2 on a 28, 1/4 the thickness and 1/4 the width full length, or not greater than 1/2 the thickness or 1/3 the width for 1/4 of the length, 1/3 the thickness and 1/3 the width full length, or not greater than 2/3 the thickness or 1/2 the width for 1/4 of the length, Checks separation across or through growth rings due to seasoning, Unlimited surface seasoning checks with through checks limited to splits, Skips surfaces that were missed or failed to clean, Maximum of 5% of the plank or 2 or less in length, Shake lengthwise separation through or between growth rings, Limited as splits if through or 2 long on the surface only, Limited as splits at ends if through or 2 long if well separated, or maximum of 3 or 1/4 the length if surface only, Warp bow, crook, cup, twist, or any combination, Sapwood stained or firm heart or red heart stain, No limit to sapwood stained or firm heart stain or red heart.